Update HTTPS port configuration and add cloudflared setup in Docker Compose

Co-authored-by: Copilot <copilot@github.com>

.docker-build.env

@@ -1,4 +1,4 @@
 NUITKA_BUILD=0
 INVENTAR_HTTP_PORT=80
-INVENTAR_HTTPS_PORT=443
-INVENTAR_APP_IMAGE=ghcr.io/aiirondev/inventarsystem:latest
+INVENTAR_HTTPS_PORT=8000
+INVENTAR_APP_IMAGE=ghcr.io/aiirondev/legendary-octo-garbanzo:latest

.github/workflows/release-docker.yml

@@ -229,8 +229,16 @@ jobs:
           cp config.json release-bundle/config.json
           cp update.sh release-bundle/update.sh
           cp init-admin.sh release-bundle/init-admin.sh
+          
+          # Multitenant scripts & docs
+          cp docker-compose-multitenant.yml release-bundle/docker-compose-multitenant.yml
+          cp docker/nginx/multitenant.conf release-bundle/docker/nginx/multitenant.conf
+          cp manage-tenant.sh release-bundle/manage-tenant.sh
+          cp run-tenant-cmd.sh release-bundle/run-tenant-cmd.sh
+          cp MULTITENANT_DEPLOYMENT.md release-bundle/MULTITENANT_DEPLOYMENT.md
+          cp MULTITENANT_PYTHON_API.md release-bundle/MULTITENANT_PYTHON_API.md
 
-          chmod +x release-bundle/start.sh release-bundle/stop.sh release-bundle/restart.sh release-bundle/backup.sh release-bundle/update.sh release-bundle/init-admin.sh
+          chmod +x release-bundle/start.sh release-bundle/stop.sh release-bundle/restart.sh release-bundle/backup.sh release-bundle/update.sh release-bundle/init-admin.sh release-bundle/manage-tenant.sh release-bundle/run-tenant-cmd.sh
           tar -czf inventarsystem-docker-bundle.tar.gz -C release-bundle .
 
       - name: Create or update GitHub Release

BOOKING_DEBUG.md

@@ -1,177 +0,0 @@
-# Fehlersuche: Geplante Ausleihen werden nicht automatisch aktiviert
-
-## 🔍 Mögliche Ursachen
-
-### 1. **Termin wurde für falsches Datum erstellt**
-Die meisten Probleme entstehen, weil der Termin für ein **falsches Datum** (z.B. morgen statt heute) erstellt wurde.
-
-### 2. **Scheduler läuft nicht**
-Der automatische Scheduler kann deaktiviert sein oder nicht starten.
-
-### 3. **Zeitzonen-Problem**
-Die Startzeit kann in einer anderen Zeitzone gespeichert sein als erwartet.
-
----
-
-## ✅ SOFORT-FIX: Manuell aktivieren
-
-Falls du eine geplante Ausleihe sofort aktivieren möchtest, nutze diesen Befehl auf dem Server:
-
-```bash
-docker exec inventarsystem-mongodb mongosh --eval "
-db.ausleihungen.updateOne(
-  {_id: ObjectId('BOOKING_ID_HIER')},
-  {\$set: {Status: 'active', LastUpdated: new Date()}}
-)" Inventarsystem
-```
-
-Ersetze `BOOKING_ID_HIER` mit der ID deiner Ausleihe.
-
----
-
-## 🔧 DEBUG: Alle geplanten Ausleihen anschauen
-
-Führe auf deinem Server aus:
-
-```bash
-docker exec inventarsystem-mongodb mongosh --eval "
-db.ausleihungen.find({Status: 'planned'}).pretty()
-" Inventarsystem
-```
-
-Das zeigt dir:
-- **Start**: Das gespeicherte Startdatum/Uhrzeit
-- **Periode**: Die Schulstunde (falls verwendet)
-- **Erstellungs-Zeit vs. aktuelle Zeit**: Vergleich
-
----
-
-## 🎯 PROBLEM 1: Falsches Datum beim Erstellen
-
-**Symptom**: Start-Zeit ist in der Zukunft (z.B. morgen statt heute)
-
-**Lösung**: 
-1. In der Kalender-Ansicht das **richtige Datum** auswählen
-2. Die **aktuelle Uhrzeit** für den Beginn nutzen (nicht eine zukünftige Zeit)
-3. Für Schulstunden: Stelle sicher die **heutige Schulstunde** zu wählen
-
----
-
-## 🎯 PROBLEM 2: Scheduler läuft nicht
-
-**Symptom**: Keine Logs über Termin-Aktivierungen
-
-**Überprüfung**:
-
-```bash
-# 1. Container-Logs anschauen
-docker logs inventarsystem-app | grep -i "scheduler\|appointment\|status update"
-
-# 2. Scheduler ist aktiviert?
-docker exec inventarsystem-app python3 -c "
-import sys
-sys.path.insert(0, '/app/Web')
-import settings as cfg
-print(f'Scheduler aktiviert: {cfg.SCHEDULER_ENABLED}')
-print(f'Scheduler Intervall: {cfg.SCHEDULER_INTERVAL_MIN} Minuten')
-"
-```
-
-**Lösung wenn deaktiviert**:
-- In `config.json` ändern:
-  ```json
-  "scheduler": {
-    "enabled": true,
-    "interval_minutes": 1
-  }
-  ```
-- Container neu starten: `docker-compose restart app`
-
----
-
-## 🎯 PROBLEM 3: Startzeit als nur-Zeit (kein Datum)
-
-**Symptom**: Start-Zeit zeigt nur "13:30" ohne Datum
-
-**Überprüfung**: In der Datenbank nach `{Start: {$type: "string"}}` suchen statt datetime
-
-**Lösung**: Die Ausleihe muss mit einem vollständigen Datum+Uhrzeit erstellt werden.
-
----
-
-## 🚀 AUTOMATISCHE AKTIVIERUNG TESTEN
-
-Nach dem Fix: Erstelle eine Ausleihe für:
-- **Heute** (das aktuelle Datum)
-- **Schulstunde 7** (13:30-14:15)
-- Startzeitpunkt sollte **jetzt oder in 1 Minute** sein
-
-Warte 2 Minuten. Der Status sollte von `planned` zu `active` wechseln.
-
----
-
-## 📊 SCHEDULER STATUS ÜBERPRÜFEN
-
-```bash
-# Zeige die letzten 50 Log-Zeilen
-docker logs --tail 50 inventarsystem-app | tail -20
-
-# Suche nach "Appointment status update"
-docker logs inventarsystem-app 2>/dev/null | grep -i "Appointment status" | tail -5
-```
-
-Erwartete Log-Ausgabe:
-```
-Appointment status update finished: X changed (Y active, Z completed)
-```
-
----
-
-## 🔍 DETAILLIERTE DEBUG-INFOS
-
-Wenn obiges nicht funktioniert, führe dies aus:
-
-```bash
-docker exec inventarsystem-app python3 -c "
-from pymongo import MongoClient
-import datetime
-
-client = MongoClient('mongodb', 27017)
-db = client['Inventarsystem']
-aus = db['ausleihungen']
-
-print('=== GEPLANTE AUSLEIHEN ===')
-for b in aus.find({'Status': 'planned'}).limit(3):
-    print(f\"Start: {b.get('Start')} | Typ: {type(b.get('Start')).__name__}\")
-    print(f\"Periode: {b.get('Period')} | User: {b.get('User')}\")
-    print(f\"Jetzt > Start? {datetime.datetime.now() > b.get('Start', datetime.datetime.max)}\")
-    print()
-"
-```
-
----
-
-## 💡 EMPFOHLENE EINSTELLUNG FÜR SCHULEN
-
-In `config.json` verwende diese Werte:
-
-```json
-{
-  "scheduler": {
-    "enabled": true,
-    "interval_minutes": 1,
-    "backup_interval_hours": 24
-  }
-}
-```
-
-Dies checkt **jede Minute** ob Termine aktiviert werden sollen - perfekt für Schulstunden.
-
----
-
-## Weitere Hilfe?
-
-Falls das nicht funktioniert:
-1. Schreib mir die **exakte Uhrzeit** wann du die Ausleihe erstellt hast
-2. Und wann sie hätte aktiviert werden sollen
-3. Zeige mir ein Beispiel aus der DB mit `docker exec inventarsystem-mongodb mongosh...`

MULTITENANT_DEPLOYMENT.md

@@ -452,3 +452,44 @@ Für Support: Siehe Legal/LICENSE
 ---
 
 **Version**: 1.0 | **Letzte Aktualisierung**: 2026-04-17 | **Kompatibilität**: Python 3.11+, MongoDB 7.0+, Redis 7+
+
+## Tenant Management Operationen (manage-tenant.sh)
+
+Um einzelne Tenants im Multi-Tenant-Umfeld im laufenden Betrieb und ohne globale Downtime zu verwalten, kann das neue CLI-Skript `manage-tenant.sh` verwendet werden.
+
+### 1. Neuen Tenant hinzufügen
+Initialisiert die MongoDB-Datenbankstruktur isoliert für einen neuen Tenant und legt initiale Admin-Zugangsdaten an.
+```bash
+./manage-tenant.sh add <tenant_id>
+```
+
+### 2. Bestimmten Tenant neu starten (Soft-Restart)
+Erzwingt sofortigen Logout und einen Cache/Session-Reset für die Nutzer *eines spezifischen* Tenants, ohne andere laufende Instanzen zu beeinträchtigen. Ideal bei Konfigurationsänderungen oder feststeckenden Sessions.
+```bash
+./manage-tenant.sh restart-tenant <tenant_id>
+```
+
+### 3. Tenant sicher entfernen
+Löscht die dedizierte MongoDB-Datenbank des gewählten Tenants vollständig (erfordert Bestätigung).
+```bash
+./manage-tenant.sh remove <tenant_id>
+```
+
+### 4. Globale Operationen
+```bash
+# Zeigt alle aktiven isolierten Tenant-Datenbanken an
+./manage-tenant.sh list
+
+# Führt einen Zero-Downtime Rolling-Restart aller Application-Container durch
+./manage-tenant.sh restart-all
+```
+
+---
+
+## Aktuelle UI- & Funktionsoptimierungen (Release April 2026)
+
+Neben der Docker-Auslagerung wurden spezifische Caching-, Parsing-, und DOM-Tricks integriert, die das Setup weiter entschlacken:
+
+* **DOM Array Slicing für Bilder:** Bei großen Beständen (hunderte Artikel) rendert der Client im Listen/Kachel-Modus künftig nur noch das primäre Bild (`slice(0, 1)`), was den DOM-Memory-Footprint drastisch reduziert und das Einfrieren von Browsern verhindert.
+* **Auto-Ingestion von Excel-Filtern:** Der Excel-Importer prüft nun dynamisch neue `categories/filter`, die noch nicht in der Datenbank existieren, und speichert sie direkt in die MongoDB `filter_presets`-Kollektion (Zero-Config für Administratoren).
+* **Responsive UI Synchronisierung:** Die Standardansicht (`main.html`) der Smartphones wurde CSS-technisch exakt an das skalierungsfähigere Profil der Admin-Mobile-Ansicht (`main_admin.html`) angeglichen.

MULTITENANT_INTEGRATION.md

@@ -322,6 +322,32 @@ INVENTAR_WORKER_CONNECTIONS=100
 
 ---
 
+## Schul-Konfiguration pro Tenant
+
+Die Datei `config.json` unterstützt jetzt einen `tenants`-Block. Damit kann jede Schule eigene Modul-Schalter bekommen, ohne dass das ganze System global umgestellt werden muss.
+
+```json
+{
+    "tenants": {
+        "schule1": {
+            "modules": {
+                "library": { "enabled": true },
+                "student_cards": { "enabled": false }
+            }
+        },
+        "schule2": {
+            "modules": {
+                "library": { "enabled": false }
+            }
+        }
+    }
+}
+```
+
+Wenn ein Request über Subdomain oder `X-Tenant-ID` aufgelöst wird, liest die App diese Werte automatisch aus und blendet die Bibliothek bzw. andere Module nur für diesen Tenant ein oder aus.
+
+---
+
 ## Support & Debugging
 
 **Fragen?**

MULTITENANT_PYTHON_API.md

@@ -0,0 +1,128 @@
+# Multi-Tenant Python Management API
+
+This document explains how the multi-tenant architecture isolates data within Python, what the return values are, and how developers can build internal administrative scripts using native Python instead of the Docker CLI. 
+
+## 1. Architectural Concept
+
+In the system, each "tenant" is essentially a dedicated MongoDB database identified by a dynamically generated string based on a subdomain or header (`inventar_<tenant_id>`). 
+App containers share a connection pool using `pymongo.MongoClient`, and requests are routed to specific databases dynamically based on the current Flask `g.tenant_context`.
+
+All MongoDB administrative tasks (creating tenants, restarting apps, fetching lists) are done via standard MongoDB Python drivers because the core multi-tenancy happens at the **database level**.
+
+## 2. Managing Tenants via Python
+
+If you want to perform multi-tenant administrative operations without traversing through `manage-tenant.sh`, you can execute native Python scripts connecting to the system's `MongoClient`.
+
+### Basic Connection Boilerplate
+Whenever automating an administrative task in Python, you simply need to connect to MongoDB using the properties defined in `settings.py`.
+
+```python
+import sys
+import os
+
+# Append Web folder so we can access configuration
+sys.path.insert(0, '/app/Web')
+import settings
+from pymongo import MongoClient
+
+# Establish connection pooling
+client = MongoClient(settings.MONGODB_HOST, int(settings.MONGODB_PORT))
+```
+
+### A. Adding a New Tenant (Database Initialization)
+A new tenant database isn’t provisioned until the first actual data insert happens. We trigger this manually by creating an `admin` user for them.
+
+**Operation:**
+```python
+def create_tenant(tenant_id, admin_password="hashed_password_here"):
+    db_name = f"{settings.MONGODB_DB}_{tenant_id}"
+    db = client[db_name]
+    
+    # MongoDB creates the DB automatically on first insert
+    result = db.users.insert_one({
+        'username': 'admin',
+        'password': admin_password,
+        'role': 'admin'
+    })
+    return result.inserted_id # Returns the BSON ObjectId of the new user
+```
+
+### B. List Active Tenants
+To find out how many isolated tenants have active databases, you query the raw `MongoClient` for all databases and search for your configured MongoDB prefix (default: `inventar_`).
+
+**Operation:**
+```python
+def list_tenants():
+    prefix = f"{settings.MONGODB_DB}_"
+    
+    # Returns a Python list of string database names
+    all_dbs = client.list_database_names() 
+    
+    # Filter and strip the prefix to return just the tenant_ids
+    active_tenants = [d.replace(prefix, "") for d in all_dbs if d.startswith(prefix)]
+    
+    return active_tenants # e.g., ['schule1', 'schule2', 'test']
+```
+
+### C. Soft-Restarting a Tenant (Invalidating Sessions)
+"Restarting" a single tenant means signing out all of their users and forcing an application refresh. Because Session data is coupled to the tenant database, dropping their `sessions` collection achieves an instant sign-out.
+
+**Operation:**
+```python
+def restart_tenant(tenant_id):
+    db_name = f"{settings.MONGODB_DB}_{tenant_id}"
+    db = client[db_name]
+    
+    # Drops the collection. All active user cookies immediately become invalid.
+    result = db.sessions.drop() 
+    
+    return result # Returns None. Raises PyMongoError if connection fails.
+```
+
+### D. Removing a Tenant Completely (Wipe Data)
+If a tenant is removed from the service or their lease expires, you can permanently obliterate their data container footprint.
+
+**Operation:**
+```python
+def remove_tenant(tenant_id):
+    db_name = f"{settings.MONGODB_DB}_{tenant_id}"
+    
+    # Erases the isolated database. Can't be undone.
+    client.drop_database(db_name) 
+    
+    return True # Returns True. Raises PyMongoError if connection fails.
+```
+
+## 3. Resolving Context Inside Flask (app.py)
+
+If you are building custom application endpoints inside `Web/app.py`, you shouldn't use the direct MongoDB `client` manually. Instead, you rely on the built-in Flask context manager (`Web/tenant.py`) to give you the correct isolated scope.
+
+### The `get_tenant_db()` function
+Every route must use `get_tenant_db(client)` to ensure users can only ever access their own school/domain's database.
+
+```python
+from pymongo import MongoClient
+import settings
+from tenant import get_tenant_db
+
+# Example Route
+@app.route('/api/items')
+def get_items():
+    # 1. Establish/reuse pooling connection
+    client = MongoClient(settings.MONGODB_HOST, settings.MONGODB_PORT)
+    
+    # 2. Get the dynamically routed DB for THIS user 
+    # (Based on Nginx Subdomain or X-Tenant-Id header)
+    db = get_tenant_db(client) 
+    
+    # 3. Runs query solely on `inventar_schule1.items`
+    items = list(db.items.find())
+    
+    return items # List of BSON Dictionaries
+```
+
+**What it returns internally:**
+The `get_tenant_db` function queries `g.tenant_context` inside Flask, calculates the database name from the subdomain, and returns a live `pymongo.database.Database` object. 
+
+This ensures that scaling is extremely cheap on resources because 1 Application Container connects to 100 separate Tenant Databases using just 1 shared `MongoClient` pool.
+

Web/app.py

@@ -339,6 +339,28 @@ def _enforce_user_permissions():
     return None
 
 
+@app.before_request
+def _enforce_active_session_user():
+    endpoint = request.endpoint or ''
+    if endpoint == 'static' or endpoint.startswith('static'):
+        return None
+
+    username = session.get('username')
+    if not username:
+        return None
+
+    user = us.get_user(username)
+    if user:
+        return None
+
+    session.clear()
+    if request.path.startswith('/api/') or request.is_json:
+        return jsonify({'ok': False, 'message': 'Sitzung ungültig. Bitte erneut anmelden.'}), 401
+
+    flash('Ihre Sitzung ist nicht mehr gültig. Bitte erneut anmelden.', 'error')
+    return redirect(url_for('login'))
+
+
 def _get_asset_version():
     """Return a cache-busting asset version tied to deployment state."""
     env_version = os.getenv('INVENTAR_ASSET_VERSION', '').strip()
@@ -2063,6 +2085,11 @@ def _upload_excel_items(scope='inventory'):
     validation_warnings = []
     reserved_codes = set()
     known_locations = set(it.get_predefined_locations())
+    known_filters = {
+        1: set(it.get_predefined_filter_values(1)),
+        2: set(it.get_predefined_filter_values(2)),
+        3: set(it.get_predefined_filter_values(3))
+    }
 
     def is_code_available(candidate_code):
         return candidate_code not in reserved_codes and it.is_code_unique(candidate_code)
@@ -2114,8 +2141,19 @@ def _upload_excel_items(scope='inventory'):
             validation_warnings.append((row_number, f'Ort "{ort}" wird neu angelegt'))
 
         filter1 = expand_filter_selection(_excel_list(val('filter1')), 1)
+        for f in filter1:
+            if f and f not in known_filters[1]:
+                validation_warnings.append((row_number, f'Kategorie 1 "{f}" wird neu angelegt'))
+
         filter2 = expand_filter_selection(_excel_list(val('filter2')), 2)
+        for f in filter2:
+            if f and f not in known_filters[2]:
+                validation_warnings.append((row_number, f'Kategorie 2 "{f}" wird neu angelegt'))
+
         filter3 = _excel_list(val('filter3'))
+        for f in filter3:
+            if f and f not in known_filters[3]:
+                validation_warnings.append((row_number, f'Kategorie 3 "{f}" wird neu angelegt'))
 
         anschaffungsjahr = _excel_int(val('anschaffungsjahr'))
         raw_year = val('anschaffungsjahr')
@@ -2217,6 +2255,21 @@ def _upload_excel_items(scope='inventory'):
             it.add_predefined_location(row['ort'])
             known_locations.add(row['ort'])
 
+        for f in row.get('filter1', []):
+            if f and f not in known_filters[1]:
+                it.add_predefined_filter_value(1, f)
+                known_filters[1].add(f)
+
+        for f in row.get('filter2', []):
+            if f and f not in known_filters[2]:
+                it.add_predefined_filter_value(2, f)
+                known_filters[2].add(f)
+
+        for f in row.get('filter3', []):
+            if f and f not in known_filters[3]:
+                it.add_predefined_filter_value(3, f)
+                known_filters[3].add(f)
+
         series_group_id = str(uuid.uuid4()) if row['count'] > 1 else None
         row_created_ids = []
 
@@ -7060,9 +7113,7 @@ def register():
             
             permission_preset = (request.form.get('permission_preset') or 'standard_user').strip()
             use_custom_permissions = request.form.get('use_custom_permissions') == 'on'
-            is_student = bool(request.form.get('is_student')) if cfg.STUDENT_CARDS_MODULE_ENABLED else False
-            student_card_id = us.normalize_student_card_id(request.form.get('student_card_id')) if cfg.STUDENT_CARDS_MODULE_ENABLED else ''
-            max_borrow_days_raw = request.form.get('max_borrow_days') if cfg.STUDENT_CARDS_MODULE_ENABLED else None
+            
             if not username or not password or not name or not last_name:
                 flash('Bitte füllen Sie alle Felder aus', 'error')
                 return redirect(url_for('register'))
@@ -7081,28 +7132,14 @@ def register():
                 for endpoint_name, _ in PERMISSION_PAGE_OPTIONS:
                     page_permissions[endpoint_name] = request.form.get(f'page_{endpoint_name}') == 'on'
 
-            max_borrow_days = None
-            if is_student:
-                if not student_card_id:
-                    flash('Für Schüler muss eine Ausweis-ID angegeben werden.', 'error')
-                    return redirect(url_for('register'))
-                if us.student_card_exists(student_card_id):
-                    flash('Die Ausweis-ID ist bereits vergeben.', 'error')
-                    return redirect(url_for('register'))
-                try:
-                    max_borrow_days = int(max_borrow_days_raw) if max_borrow_days_raw else cfg.STUDENT_DEFAULT_BORROW_DAYS
-                except (TypeError, ValueError):
-                    max_borrow_days = cfg.STUDENT_DEFAULT_BORROW_DAYS
-                max_borrow_days = max(1, min(max_borrow_days, cfg.STUDENT_MAX_BORROW_DAYS))
-
             us.add_user(
                 username,
                 password,
                 name,
                 last_name,
-                is_student=is_student,
-                student_card_id=student_card_id if is_student else None,
-                max_borrow_days=max_borrow_days,
+                is_student=False,
+                student_card_id=None,
+                max_borrow_days=None,
                 permission_preset=permission_preset,
                 action_permissions=action_permissions,
                 page_permissions=page_permissions,

Web/ausleihung.py

@@ -71,6 +71,10 @@ def get_current_status(ausleihung, log_changes=False, user=None):
     # Bei stornierten Ausleihungen bleibt der Status immer storniert
     if original_status == 'cancelled':
         return 'cancelled'
+        
+    # Wenn die Ausleihung bereits abgeschlossen ist, bleibt sie es
+    if original_status == 'completed':
+        return 'completed'
     
     current_time = datetime.datetime.now()
     start_time = ausleihung.get('Start')
@@ -79,10 +83,6 @@ def get_current_status(ausleihung, log_changes=False, user=None):
     # Wenn kein Startdatum vorhanden ist, Status auf 'planned' setzen
     if not start_time:
         new_status = 'planned'
-    # Wenn die Ausleihung als 'completed' markiert wurde und ein Enddatum hat,
-    # bleibt sie bei 'completed'
-    elif original_status == 'completed' and end_time:
-        new_status = 'completed'
     # Wenn die aktuelle Zeit vor dem Startdatum liegt, ist die Ausleihung geplant
     elif current_time < start_time:
         # DEBUG: Log info wenn Booking noch lange in der Zukunft ist

Web/push_notifications.py

@@ -324,7 +324,8 @@ def _send_web_push_notification(subscription, payload):
             data=json.dumps(payload),
             vapid_private_key=VAPID_PRIVATE_KEY,
             vapid_claims={'sub': VAPID_SUBJECT},
-            timeout=10
+            timeout=10,
+            ttl=3600  # Notification expires after 1 hour if device is offline
         )
         
         return True

Web/requirements.txt

@@ -15,3 +15,4 @@ python-barcode
 openpyxl
 cryptography
 pywebpush
+py-vapid==1.9.0

Web/settings.py

@@ -157,8 +157,36 @@ SSL_KEY = _get(_conf, ['ssl', 'key'], DEFAULTS['ssl']['key'])
 SCHOOL_PERIODS = _get(_conf, ['schoolPeriods'], DEFAULTS['schoolPeriods'])
 
 # Optional feature modules
-LIBRARY_MODULE_ENABLED = bool(_get(_conf, ['modules', 'library', 'enabled'], DEFAULTS['modules']['library']['enabled']))
-STUDENT_CARDS_MODULE_ENABLED = bool(_get(_conf, ['modules', 'student_cards', 'enabled'], DEFAULTS['modules']['student_cards']['enabled']))
+TENANT_CONFIGS = _get(_conf, ['tenants'], {})
+
+
+class _TenantAwareBool:
+    def __init__(self, module_name, default):
+        self.module_name = module_name
+        self.default = bool(default)
+
+    def resolve(self):
+        try:
+            from tenant import is_tenant_module_enabled
+            return bool(is_tenant_module_enabled(self.module_name, default=self.default))
+        except Exception:
+            return self.default
+
+    def __bool__(self):
+        return self.resolve()
+
+    def __int__(self):
+        return int(self.resolve())
+
+    def __str__(self):
+        return 'True' if self.resolve() else 'False'
+
+    def __repr__(self):
+        return f"_TenantAwareBool(module_name={self.module_name!r}, value={self.resolve()!r})"
+
+
+LIBRARY_MODULE_ENABLED = _TenantAwareBool('library', _get(_conf, ['modules', 'library', 'enabled'], DEFAULTS['modules']['library']['enabled']))
+STUDENT_CARDS_MODULE_ENABLED = _TenantAwareBool('student_cards', _get(_conf, ['modules', 'student_cards', 'enabled'], DEFAULTS['modules']['student_cards']['enabled']))
 STUDENT_DEFAULT_BORROW_DAYS = int(_get(_conf, ['modules', 'student_cards', 'default_borrow_days'], DEFAULTS['modules']['student_cards']['default_borrow_days']))
 STUDENT_MAX_BORROW_DAYS = int(_get(_conf, ['modules', 'student_cards', 'max_borrow_days'], DEFAULTS['modules']['student_cards']['max_borrow_days']))
 

Web/static/css/styles.css

@@ -21,6 +21,47 @@
     --ui-radius: 12px;
 }
 
+:root[data-theme="dark"] {
+    --ui-bg: #0f172a;
+    --ui-bg-accent: #1e293b;
+    --ui-surface: #1e293b;
+    --ui-surface-soft: #25314a;
+    --ui-border: #334155;
+    --ui-text: #f1f5f9;
+    --ui-text-muted: #94a3b8;
+    --ui-title: #ffffff;
+    --ui-shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.4);
+    --ui-shadow-md: 0 10px 24px rgba(0, 0, 0, 0.5);
+}
+
+/* Safe Area Support for iPad notches, Dynamic Island, and rounded corners */
+html {
+    /* Ensure viewport-fit is respected */
+    viewport-fit: cover;
+}
+
+body {
+    /* Respect safe areas on mobile devices */
+    position: relative;
+}
+
+/* Future-proof: Support for various viewport and safe-area features */
+@supports (padding: max(0px)) {
+    body {
+        /* Ensure body padding never conflicts with safe areas */
+        padding: 0;
+    }
+}
+
+/* Make inputs visible in dark mode */
+:root[data-theme="dark"] input, 
+:root[data-theme="dark"] select, 
+:root[data-theme="dark"] textarea {
+    background-color: var(--ui-surface-soft) !important;
+    color: var(--ui-text) !important;
+    border-color: var(--ui-border) !important;
+}
+
 body {
     font-family: "Manrope", "Segoe UI", "Noto Sans", sans-serif;
     color: var(--ui-text);
@@ -92,7 +133,7 @@ span {
 .card-header,
 .modal-header,
 thead th {
-    background: linear-gradient(180deg, #f7fafd, #edf3f8) !important;
+    background: var(--ui-surface-soft) !important;
     border-bottom: 1px solid var(--ui-border) !important;
     color: var(--ui-title) !important;
 }
@@ -107,10 +148,10 @@ input[type="email"],
 input[type="date"],
 select {
     border-radius: 10px !important;
-    border: 1px solid #cad5e0 !important;
+    border: 1px solid var(--ui-border) !important;
     min-height: 40px;
     color: var(--ui-text) !important;
-    background-color: #fff !important;
+    background-color: var(--ui-surface) !important;
     transition: border-color 0.15s ease, box-shadow 0.15s ease;
 }
 
@@ -131,11 +172,13 @@ select:focus {
 .table th,
 .table td {
     vertical-align: middle;
-    border-color: #dee6ee !important;
+    border-color: var(--ui-border) !important;
+    background-color: var(--ui-surface) !important;
+    color: var(--ui-text) !important;
 }
 
 .table-striped > tbody > tr:nth-of-type(odd) {
-    background-color: #f8fbff;
+    background-color: var(--ui-surface-soft) !important;
 }
 
 .alert {
@@ -144,13 +187,20 @@ select:focus {
 }
 
 .navbar {
-    border-bottom: 1px solid #273341;
+    border-bottom: 1px solid var(--ui-border);
     box-shadow: none;
+    -webkit-backdrop-filter: blur(10px);
+    backdrop-filter: blur(10px);
+    /* Safe area insets for iPad notches and Dynamic Island */
+    padding-left: env(safe-area-inset-left, 0);
+    padding-right: env(safe-area-inset-right, 0);
 }
 
 .navbar-brand {
     font-weight: 800;
     letter-spacing: 0.02em;
+    /* Prevent navbar brand from extending into unsafe areas */
+    word-break: break-word;
 }
 
 @media (max-width: 900px) {
@@ -164,21 +214,48 @@ select:focus {
     }
 }
 
-/* Edit and generate buttons with black text for better visibility */
-.edit-button {
-    color: black !important; /* Override any existing color */
+/* Mobile and tablet safe area handling for navbar */
+@media (max-width: 992px) {
+    .navbar {
+        /* Ensure navbar spans full width but respects safe areas */
+        width: 100vw;
+        margin-left: calc(-50vw + 50%);
+        /* Safe area padding is already handled by navbar class */
+    }
+    
+    .navbar .container-fluid {
+        width: 100%;
+        box-sizing: border-box;
+        /* Ensure padding accounts for safe areas on small screens */
+        padding-left: max(env(safe-area-inset-left, 0), 12px);
+        padding-right: max(env(safe-area-inset-right, 0), 12px);
+    }
+    
+    .navbar-collapse {
+        /* Ensure collapsed navbar respects safe areas */
+        padding-left: env(safe-area-inset-left, 0);
+        padding-right: env(safe-area-inset-right, 0);
+    }
 }
 
-.duplicate-button {
-    color: black !important; /* Override any existing color */
+/* iPad-specific landscape and portrait handling */
+@media (max-height: 600px) and (orientation: landscape) {
+    .navbar {
+        padding-top: max(env(safe-area-inset-top, 0), 4px);
+    }
+    
+    .navbar .container-fluid {
+        padding-bottom: 4px;
+    }
 }
 
-.generate-qr-button {
-    color: black !important; /* Override any existing color */
+/* Edit and generate buttons with theme-aware text for better visibility */
+.edit-button, .duplicate-button, .generate-qr-button {
+    color: var(--ui-text) !important; /* Override any existing color */
 }
 
 .ausleihen {
-    color: black !important; /* Override any existing color */
+    /* Color handled securely below */
 }
 
 /* Modal image display fix */
@@ -245,12 +322,12 @@ select:focus {
 .view-toggle-btn {
     width: 38px;
     height: 38px;
-    border: 1px solid #c7ced6;
+    border: 1px solid var(--ui-border);
     border-radius: 50%;
-    background: #ffffff;
+    background: var(--ui-surface);
     font-size: 1.15rem;
     cursor: pointer;
-    color: #2f3e4e;
+    color: var(--ui-text);
     display: inline-flex;
     align-items: center;
     justify-content: center;
@@ -259,8 +336,8 @@ select:focus {
 
 .view-toggle-btn:hover {
     transform: translateY(-1px);
-    border-color: #8fa2b7;
-    background: #f8fbff;
+    border-color: var(--ui-border);
+    background: var(--ui-surface-soft);
     box-shadow: 0 3px 8px rgba(33, 37, 41, 0.12);
 }
 
@@ -269,9 +346,9 @@ select:focus {
 }
 
 .view-toggle-btn[aria-pressed='true'] {
-    background: #e9f2ff;
-    border-color: #7ea1c8;
-    color: #1f4f7a;
+    background: var(--module-primary-color);
+    border-color: var(--module-primary-color);
+    color: white;
 }
 
 .table-view-header {
@@ -288,7 +365,7 @@ body.table-view .table-view-header {
     border: 0;
     border-radius: 10px;
     background: transparent;
-    color: #3f4e5d;
+    color: var(--ui-text-muted);
     font-size: 0.82rem;
     font-weight: 700;
     text-transform: uppercase;
@@ -307,9 +384,9 @@ body.table-view .item-card {
     max-width: none;
     margin: 0 0 10px 0;
     padding: 12px 14px;
-    border: 1px solid #e1e6ed;
+    border: 1px solid var(--ui-border);
     border-radius: 10px;
-    background: #ffffff;
+    background: var(--ui-surface);
     box-shadow: none;
     scroll-snap-align: none;
 }
@@ -335,7 +412,7 @@ body.table-view .item-card .card-content .item-name-cell,
 body.table-view .item-card .card-content .item-col-name {
     font-size: 0.98rem;
     font-weight: 700;
-    color: #1f2d3d;
+    color: var(--ui-title);
     white-space: nowrap;
     overflow: hidden;
     text-overflow: ellipsis;
@@ -352,7 +429,7 @@ body.table-view .item-card .card-content .item-col-filter3,
 body.table-view .item-card .card-content .item-code-cell,
 body.table-view .item-card .card-content .item-col-code,
 body.table-view .item-card .card-content .item-col-count {
-    color: #445465;
+    color: var(--ui-text-muted);
     font-size: 0.9rem;
     white-space: nowrap;
     overflow: hidden;
@@ -369,7 +446,7 @@ body.table-view .item-card .damage-badge {
 body.table-view .item-card .actions {
     margin-top: 10px;
     padding-top: 10px;
-    border-top: 1px dashed #d9e0e8;
+    border-top: 1px dashed var(--ui-border);
 }
 
 @media (max-width: 900px) {
@@ -805,4 +882,17 @@ body.table-view .item-card .actions {
         padding: 7px 12px !important;
         font-size: 0.84rem !important;
     }
-}
+}
+/* iOS and Mobile optimization fixes */
+html, body {
+    -webkit-text-size-adjust: 100%;
+    -webkit-tap-highlight-color: transparent;
+}
+.scrollable-container, .items-container {
+    -webkit-overflow-scrolling: touch;
+}
+@supports (padding-bottom: env(safe-area-inset-bottom)) {
+    .fixed-bottom, .modal-footer {
+        padding-bottom: env(safe-area-inset-bottom);
+    }
+}

Web/static/manifest.json

@@ -1,134 +1,23 @@
 {
-  "name": "Inventarsystem",
-  "short_name": "Inventar",
-  "description": "Verwaltungssystem für Schulinventare mit Ausleihmanagement",
+  "name": "Ausleihsystem",
+  "short_name": "Ausleihe",
+  "description": "System zur Verwaltung von Ausleihen",
   "start_url": "/",
-  "scope": "/",
   "display": "standalone",
-  "orientation": "portrait-primary",
   "background_color": "#ffffff",
-  "theme_color": "#007bff",
-  "dir": "ltr",
-  "lang": "de-DE",
-  "prefer_related_applications": false,
-  "related_applications": [],
+  "theme_color": "#1f2937",
   "icons": [
     {
-      "src": "/static/img/logo-72x72.png",
-      "sizes": "72x72",
+      "src": "/static/img/icon-192.png",
       "type": "image/png",
-      "purpose": "any"
-    },
-    {
-      "src": "/static/img/logo-96x96.png",
-      "sizes": "96x96",
-      "type": "image/png",
-      "purpose": "any"
-    },
-    {
-      "src": "/static/img/logo-128x128.png",
-      "sizes": "128x128",
-      "type": "image/png",
-      "purpose": "any"
-    },
-    {
-      "src": "/static/img/logo-144x144.png",
-      "sizes": "144x144",
-      "type": "image/png",
-      "purpose": "any"
-    },
-    {
-      "src": "/static/img/logo-152x152.png",
-      "sizes": "152x152",
-      "type": "image/png",
-      "purpose": "any"
-    },
-    {
-      "src": "/static/img/logo-192x192.png",
       "sizes": "192x192",
-      "type": "image/png",
-      "purpose": "any"
+      "purpose": "any maskable"
     },
     {
-      "src": "/static/img/logo-384x384.png",
-      "sizes": "384x384",
+      "src": "/static/img/icon-512.png",
       "type": "image/png",
-      "purpose": "any"
-    },
-    {
-      "src": "/static/img/logo-512x512.png",
       "sizes": "512x512",
-      "type": "image/png",
-      "purpose": "any"
-    },
-    {
-      "src": "/static/img/logo-192x192-maskable.png",
-      "sizes": "192x192",
-      "type": "image/png",
-      "purpose": "maskable"
-    },
-    {
-      "src": "/static/img/logo-512x512-maskable.png",
-      "sizes": "512x512",
-      "type": "image/png",
-      "purpose": "maskable"
+      "purpose": "any maskable"
     }
-  ],
-  "screenshots": [
-    {
-      "src": "/static/img/screenshot-540x720.png",
-      "sizes": "540x720",
-      "type": "image/png",
-      "form_factor": "narrow"
-    },
-    {
-      "src": "/static/img/screenshot-1280x720.png",
-      "sizes": "1280x720",
-      "type": "image/png",
-      "form_factor": "wide"
-    }
-  ],
-  "categories": ["education", "productivity"],
-  "shortcuts": [
-    {
-      "name": "Meine Ausleihungen",
-      "short_name": "Ausleihungen",
-      "description": "Zeige meine aktuellen Ausleihungen",
-      "url": "/my_borrowed_items",
-      "icons": [
-        {
-          "src": "/static/img/shortcut-96x96.png",
-          "sizes": "96x96"
-        }
-      ]
-    },
-    {
-      "name": "Kalender",
-      "short_name": "Kalender",
-      "description": "Kalender für Ausleihplanungen",
-      "url": "/terminplan",
-      "icons": [
-        {
-          "src": "/static/img/shortcut-96x96.png",
-          "sizes": "96x96"
-        }
-      ]
-    }
-  ],
-  "share_target": {
-    "action": "/share",
-    "method": "POST",
-    "enctype": "multipart/form-data",
-    "params": {
-      "title": "title",
-      "text": "text",
-      "url": "url",
-      "files": [
-        {
-          "name": "media",
-          "accept": ["image/*", "video/*"]
-        }
-      ]
-    }
-  }
+  ]
 }

Web/static/sw.js

@@ -0,0 +1,18 @@
+const CACHE_NAME = 'ausleihe-cache-v1';
+
+self.addEventListener('install', (event) => {
+    self.skipWaiting();
+});
+
+self.addEventListener('activate', (event) => {
+    event.waitUntil(clients.claim());
+});
+
+self.addEventListener('fetch', (event) => {
+    // Einfacher Fallback aufs Netzwerk (Offline-Seite könnte hier ergänzt werden)
+    event.respondWith(
+        fetch(event.request).catch(() => {
+            return caches.match(event.request);
+        })
+    );
+});

Web/templates/admin_audit.html

@@ -11,7 +11,7 @@
   </div>
 
   <div style="display:grid; grid-template-columns:repeat(auto-fit,minmax(220px,1fr)); gap:12px; margin:16px 0 20px;">
-    <div style="padding:14px; border:1px solid #e2e8f0; border-radius:10px; background:#fff;">
+    <div style="padding:14px; border:1px solid #e2e8f0; border-radius:10px; background: var(--ui-surface);">
       <div style="font-size:0.85rem; color:#64748b;">Chain Status</div>
       {% if verify_result.ok %}
       <div style="font-size:1.35rem; font-weight:700; color:#166534;">OK</div>
@@ -19,15 +19,15 @@
       <div style="font-size:1.35rem; font-weight:700; color:#991b1b;">FEHLER</div>
       {% endif %}
     </div>
-    <div style="padding:14px; border:1px solid #e2e8f0; border-radius:10px; background:#fff;">
+    <div style="padding:14px; border:1px solid #e2e8f0; border-radius:10px; background: var(--ui-surface);">
       <div style="font-size:0.85rem; color:#64748b;">Einträge</div>
       <div style="font-size:1.35rem; font-weight:700;">{{ verify_result.count }}</div>
     </div>
-    <div style="padding:14px; border:1px solid #e2e8f0; border-radius:10px; background:#fff;">
+    <div style="padding:14px; border:1px solid #e2e8f0; border-radius:10px; background: var(--ui-surface);">
       <div style="font-size:0.85rem; color:#64748b;">Letzter Index</div>
       <div style="font-size:1.35rem; font-weight:700;">{{ verify_result.last_chain_index }}</div>
     </div>
-    <div style="padding:14px; border:1px solid #e2e8f0; border-radius:10px; background:#fff;">
+    <div style="padding:14px; border:1px solid #e2e8f0; border-radius:10px; background: var(--ui-surface);">
       <div style="font-size:0.85rem; color:#64748b;">Mismatch Count</div>
       <div style="font-size:1.35rem; font-weight:700;">{{ verify_result.mismatches|length }}</div>
     </div>
@@ -61,7 +61,7 @@
   </div>
   {% endif %}
 
-  <div style="border:1px solid #e2e8f0; border-radius:10px; background:#fff; padding:12px;">
+  <div style="border:1px solid #e2e8f0; border-radius:10px; background: var(--ui-surface); padding:12px;">
     <h3 style="margin-top:0;">Letzte Audit-Ereignisse</h3>
     <div style="max-height:560px; overflow:auto;">
       <table class="table" style="width:100%; border-collapse:collapse;">

Web/templates/admin_borrowings.html

@@ -161,7 +161,7 @@
 </div>
 
 <div id="invoice-modal" style="display:none; position:fixed; inset:0; background:rgba(15,23,42,0.72); z-index:9999; padding:20px; overflow:auto;">
-  <div style="max-width:760px; margin:40px auto; background:#fff; border-radius:12px; padding:24px; box-shadow:0 20px 60px rgba(0,0,0,0.3);">
+  <div style="max-width:760px; margin:40px auto; background: var(--ui-surface); border-radius:12px; padding:24px; box-shadow:0 20px 60px rgba(0,0,0,0.3);">
     <div style="display:flex; justify-content:space-between; align-items:center; gap:12px; margin-bottom:18px;">
       <div>
         <h2 style="margin:0;">Rechnung erstellen</h2>
@@ -174,15 +174,15 @@
       <div style="display:grid; grid-template-columns:repeat(auto-fit, minmax(240px, 1fr)); gap:16px; margin-bottom:16px;">
         <div>
           <label for="invoice-item" style="display:block; font-weight:700; margin-bottom:6px;">Element</label>
-          <input id="invoice-item" type="text" readonly style="width:100%; padding:10px; border:1px solid #ddd; border-radius:6px; background:#f8fafc;">
+          <input id="invoice-item" type="text" readonly style="width:100%; padding:10px; border:1px solid #ddd; border-radius:6px; background: var(--ui-surface-soft);">
         </div>
         <div>
           <label for="invoice-borrower" style="display:block; font-weight:700; margin-bottom:6px;">Schüler</label>
-          <input id="invoice-borrower" type="text" readonly style="width:100%; padding:10px; border:1px solid #ddd; border-radius:6px; background:#f8fafc;">
+          <input id="invoice-borrower" type="text" readonly style="width:100%; padding:10px; border:1px solid #ddd; border-radius:6px; background: var(--ui-surface-soft);">
         </div>
         <div>
           <label for="invoice-code" style="display:block; font-weight:700; margin-bottom:6px;">Element-ID / Code</label>
-          <input id="invoice-code" type="text" readonly style="width:100%; padding:10px; border:1px solid #ddd; border-radius:6px; background:#f8fafc;">
+          <input id="invoice-code" type="text" readonly style="width:100%; padding:10px; border:1px solid #ddd; border-radius:6px; background: var(--ui-surface-soft);">
         </div>
         <div>
           <label for="invoice-amount" style="display:block; font-weight:700; margin-bottom:6px;">Preis</label>

Web/templates/admin_damaged_items.html

@@ -17,14 +17,14 @@
     </div>
   </div>
 
-  <div style="background:#fff; border:1px solid #e2e8f0; border-radius:14px; padding:14px; margin-bottom:12px;">
+  <div style="background: var(--ui-surface); border:1px solid #e2e8f0; border-radius:14px; padding:14px; margin-bottom:12px;">
     <input id="damage-search" type="text" placeholder="Suche nach Name, Code, Typ, Benutzer oder Schaden..." style="width:100%; padding:10px 12px; border:1px solid #d1d5db; border-radius:10px;">
   </div>
 
-  <div style="background:#fff; border:1px solid #e2e8f0; border-radius:14px; padding:0; overflow:hidden;">
+  <div style="background: var(--ui-surface); border:1px solid #e2e8f0; border-radius:14px; padding:0; overflow:hidden;">
     <table id="damage-table" style="width:100%; border-collapse:collapse;">
       <thead>
-        <tr style="background:#f8fafc;">
+        <tr style="background: var(--ui-surface-soft);">
           <th style="text-align:left; padding:11px; border-bottom:1px solid #e5e7eb;">Item</th>
           <th style="text-align:left; padding:11px; border-bottom:1px solid #e5e7eb;">Status</th>
           <th style="text-align:left; padding:11px; border-bottom:1px solid #e5e7eb;">Letzte Meldung</th>

Web/templates/base.html

@@ -10,10 +10,24 @@
 <html lang="de" data-module="{{ CURRENT_MODULE }}">
 <head>
     <meta charset="UTF-8">
-    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=5.0, user-scalable=yes">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=5.0, user-scalable=yes, viewport-fit=cover">
     <meta name="mobile-web-app-capable" content="yes">
     <meta name="apple-mobile-web-app-capable" content="yes">
     <meta name="apple-mobile-web-app-status-bar-style" content="black-translucent">
+    <meta name="theme-color" content="#2c3e50" id="meta-theme-color">
+    <script>
+        // Init theme early to prevent FOUC (Flash of Unstyled Content)
+        (function() {
+            var theme = localStorage.getItem('inventarsystem-theme');
+            if (theme === 'dark' || (!theme && window.matchMedia && window.matchMedia('(prefers-color-scheme: dark)').matches)) {
+                document.documentElement.setAttribute('data-theme', 'dark');
+                document.getElementById('meta-theme-color').setAttribute('content', '#1a252f');
+            } else {
+                document.documentElement.setAttribute('data-theme', 'light');
+                document.getElementById('meta-theme-color').setAttribute('content', '#2c3e50');
+            }
+        })();
+    </script>
     <meta name="csrf-token" content="{{ csrf_token }}">
     <title>{% block title %}Inventarsystem{% endblock %}</title>
     {% block head %}
@@ -102,6 +116,9 @@
             --module-accent-color: #3498db;
             --module-accent-light: rgba(52, 152, 219, 0.1);
             --module-brand-icon: "📦";
+            --page-bg-gradient: linear-gradient(180deg, #f2f5f8, #e7edf4);
+            --page-bg-overlay1: rgba(86, 145, 200, 0.08);
+            --page-bg-overlay2: rgba(52, 98, 150, 0.09);
         }
 
         html[data-module="library"] {
@@ -112,17 +129,34 @@
             --module-brand-icon: "📚";
         }
 
+        :root[data-theme="dark"] {
+            --module-primary-color: #1a252f;
+            --module-primary-light: #2c3e50;
+            --module-accent-color: #2980b9;
+            --module-brand-icon: "📦";
+            --page-bg-gradient: linear-gradient(180deg, #0f172a, #1e293b);
+            --page-bg-overlay1: rgba(56, 189, 248, 0.05);
+            --page-bg-overlay2: rgba(59, 130, 246, 0.06);
+        }
+        
+        html[data-theme="dark"][data-module="library"] {
+            --module-primary-color: #4a354d;
+            --module-primary-light: #614666;
+            --module-accent-color: #8e44ad;
+        }
+
         /* Global styles */
         body {
             font-family: "Manrope", "Segoe UI", "Noto Sans", sans-serif;
             background:
-                radial-gradient(1200px 500px at 10% -10%, rgba(86, 145, 200, 0.08), transparent 55%),
-                radial-gradient(900px 420px at 95% 0%, rgba(52, 98, 150, 0.09), transparent 52%),
-                linear-gradient(180deg, #f2f5f8, #e7edf4);
+                radial-gradient(1200px 500px at 10% -10%, var(--page-bg-overlay1), transparent 55%),
+                radial-gradient(900px 420px at 95% 0%, var(--page-bg-overlay2), transparent 52%),
+                var(--page-bg-gradient);
             margin: 0;
             padding: 0;
-            padding-bottom: 30px;
-            color: #1f2d3d;
+            padding-bottom: auto; /* Fallback for dynamic calculation */
+            padding-bottom: env(safe-area-inset-bottom, 30px);
+            color: var(--ui-text, #1f2d3d);
         }
         
         .container {
@@ -135,29 +169,87 @@
             background-color: var(--module-primary-color) !important;
             position: sticky;
             top: 0;
+            /* iOS Safe Area insets for notches and rounded corners */
+            padding-top: env(safe-area-inset-top, 0);
+            padding-left: env(safe-area-inset-left, 0);
+            padding-right: env(safe-area-inset-right, 0);
             z-index: 1900;
         }
 
         .navbar .container-fluid {
-            gap: 10px;
+            gap: 8px;
+            /* Ensure container respects safe areas on all sides */
+            padding-left: max(env(safe-area-inset-left, 0), 12px);
+            padding-right: max(env(safe-area-inset-right, 0), 12px);
+            padding-bottom: env(safe-area-inset-bottom, 0);
         }
         
         .navbar-brand {
             font-weight: bold;
-            font-size: 1.4rem;
+            font-size: 1.3rem;
+            padding-right: 10px;
+            white-space: nowrap;
+            flex-shrink: 0;
         }
         
         .navbar-brand::before {
             content: attr(data-icon);
-            margin-right: 8px;
+            margin-right: 6px;
         }
 
         .navbar-nav .nav-link {
-            font-size: 1rem;
+            font-size: 0.95rem;
             font-weight: 600;
-            padding: 0.6rem 0.85rem;
-            border-radius: 8px;
+            padding: 0.5rem 0.75rem;
+            border-radius: 6px;
             transition: padding .18s ease, font-size .18s ease;
+            white-space: nowrap;
+        }
+
+        /* iPad/Tablet responsive adjustments */
+        @media (max-width: 1024px) {
+            .navbar .container-fluid {
+                gap: 6px;
+                padding-left: max(env(safe-area-inset-left, 0), 10px);
+                padding-right: max(env(safe-area-inset-right, 0), 10px);
+            }
+            
+            .navbar-brand {
+                font-size: 1.1rem;
+                padding-right: 8px;
+            }
+            
+            .navbar-brand::before {
+                margin-right: 4px;
+            }
+
+            .navbar-nav .nav-link {
+                font-size: 0.85rem;
+                padding: 0.45rem 0.6rem;
+            }
+        }
+
+        /* Small phones responsive adjustments */
+        @media (max-width: 576px) {
+            .navbar .container-fluid {
+                gap: 4px;
+                padding-left: max(env(safe-area-inset-left, 0), 8px);
+                padding-right: max(env(safe-area-inset-right, 0), 8px);
+            }
+            
+            .navbar-brand {
+                font-size: 0.95rem;
+                padding-right: 6px;
+            }
+            
+            .navbar-brand::before {
+                display: none;
+            }
+
+            .navbar-nav .nav-link {
+                font-size: 0.75rem;
+                padding: 0.4rem 0.5rem;
+            }
         }
 
         .navbar.nav-compact .navbar-brand {
@@ -214,6 +306,7 @@
             align-items: center;
             margin-right: 10px;
             width: min(420px, 42vw);
+            min-width: 0;
         }
 
         .function-search-form {
@@ -221,10 +314,13 @@
             display: flex;
             gap: 6px;
             align-items: center;
+            min-width: 0;
         }
 
         .function-search-input {
-            width: 100%;
+            flex: 1 1 auto;
+            width: auto;
+            min-width: 0;
             min-height: 38px;
             border-radius: 10px;
             border: 1px solid rgba(255, 255, 255, 0.3);
@@ -245,6 +341,7 @@
         }
 
         .function-search-btn {
+            flex: 0 0 auto;
             min-height: 38px;
             border-radius: 10px;
             border: 1px solid rgba(255, 255, 255, 0.45);
@@ -351,18 +448,19 @@
         
         /* Dropdown menus - consistent with system design */
         .dropdown-menu {
-            box-shadow: 0 4px 6px rgba(0,0,0,0.1);
-            border: 1px solid #dee2e6;
+            box-shadow: var(--ui-shadow-md);
+            border: 1px solid var(--ui-border);
             border-radius: 8px;
             padding: 8px 0;
             min-width: 200px;
             margin-top: 5px;
+            background-color: var(--ui-surface);
         }
         
         .dropdown-item {
             padding: 10px 16px;
             font-size: 0.9rem;
-            color: #495057;
+            color: var(--ui-text);
             transition: all 0.2s ease;
             border: none;
             background: none;
@@ -370,8 +468,8 @@
         
         .dropdown-item:hover,
         .dropdown-item:focus {
-            background-color: #f8f9fa;
-            color: #007bff;
+            background-color: var(--ui-surface-soft);
+            color: var(--module-accent-color);
             transform: translateX(2px);
         }
         
@@ -434,17 +532,60 @@
             }
             
             .nav-item.dropdown .dropdown-toggle {
-                padding: 8px 12px;
+                padding: 12px 12px;
+                min-height: 48px;
             }
 
             .navbar-toggler {
-                padding: 0.5rem 0.65rem;
+                padding: 0.6rem 0.8rem;
                 border-width: 2px;
+                min-height: 48px;
+                min-width: 48px;
+                margin-top: 4px;
+            }
+
+            .navbar-collapse {
+                width: 100%;
+            }
+
+            .navbar-collapse > .d-flex {
+                width: 100%;
+                flex-direction: column;
+                align-items: stretch;
+                gap: 8px;
             }
 
             .function-search-wrap {
                 width: 100%;
+                max-width: 100%;
                 margin: 8px 0 10px;
+                flex: 1 1 100%;
+            }
+
+            .function-search-form {
+                width: 100%;
+                max-width: 100%;
+                flex-wrap: nowrap;
+            }
+
+            .function-search-input {
+                width: auto;
+                min-width: 0;
+                flex: 1 1 auto;
+            }
+
+            .function-search-btn {
+                flex: 0 0 auto;
+                white-space: nowrap;
+            }
+
+            .navbar-text {
+                margin-right: 0 !important;
+                width: 100%;
+            }
+
+            .user-menu-wrap {
+                align-self: flex-start;
             }
 
             .navbar-nav .nav-item {
@@ -465,7 +606,7 @@
             
             /* Account dropdown stays light theme on mobile */
             .dropdown-menu-end {
-                background-color: #ffffff;
+                background-color: var(--ui-surface);
                 border: 1px solid #dee2e6;
             }
             
@@ -474,7 +615,7 @@
             }
             
             .dropdown-menu-end .dropdown-item:hover {
-                background-color: #f8f9fa;
+                background-color: var(--ui-surface-soft);
                 color: #007bff;
             }
         }
@@ -573,17 +714,38 @@
                 margin-left: auto;
                 flex: 0 0 auto;
                 align-self: flex-start;
+                min-width: 48px;
+                min-height: 48px;
+                border: none;
+                background: rgba(255, 255, 255, 0.1);
+                border-radius: 10px;
+                display: flex;
+                align-items: center;
+                justify-content: center;
+                transition: background 0.2s ease;
+            }
+            
+            .navbar-toggler:active,
+            .navbar-toggler:focus {
+                background: rgba(255, 255, 255, 0.2);
+                box-shadow: 0 0 0 2px rgba(255, 255, 255, 0.1);
             }
 
             .navbar-collapse {
                 order: 4;
                 width: 100%;
-                margin-top: 8px;
-                padding: 10px 10px 6px;
-                border-radius: 14px;
-                background: rgba(15, 23, 42, 0.18);
-                backdrop-filter: blur(10px);
-                -webkit-backdrop-filter: blur(10px);
+                margin-top: 12px;
+                padding: 12px;
+                border-radius: 16px;
+                background: rgba(15, 23, 42, 0.85);
+                box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
+                border: 1px solid rgba(255, 255, 255, 0.1);
+                backdrop-filter: blur(16px);
+                -webkit-backdrop-filter: blur(16px);
+                max-height: calc(100vh - 90px); /* fallback */
+                max-height: calc(100dvh - 90px);
+                overflow-y: auto;
+                -webkit-overflow-scrolling: touch;
             }
 
             .navbar-collapse.show,
@@ -595,7 +757,7 @@
                 width: 100%;
                 align-items: stretch;
                 gap: 8px;
-                padding-top: 2px;
+                padding-top: 4px;
             }
 
             .navbar-nav .nav-item {
@@ -605,11 +767,12 @@
             .navbar-nav .nav-link {
                 width: 100%;
                 justify-content: flex-start;
-                min-height: 46px;
-                padding: 0.8rem 0.95rem;
+                min-height: 48px;
+                padding: 0.9rem 1.1rem;
+                margin-bottom: 2px;
                 border-radius: 12px;
-                background: rgba(255, 255, 255, 0.08);
-                box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.08);
+                background: rgba(255, 255, 255, 0.06);
+                box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.05);
             }
 
             .navbar-nav .nav-link.nav-active,
@@ -632,6 +795,23 @@
                 margin-left: 0;
                 margin-top: 6px;
                 border-radius: 12px;
+                background: rgba(255, 255, 255, 0.08); /* Match nav-link slightly */
+                border: 1px solid rgba(255, 255, 255, 0.08);
+                box-shadow: none;
+            }
+
+            .navbar-nav .dropdown-item {
+                color: rgba(255, 255, 255, 0.9);
+                padding: 12px 16px;
+                border-radius: 8px;
+                margin: 2px 8px;
+                width: calc(100% - 16px);
+            }
+
+            .navbar-nav .dropdown-item:hover,
+            .navbar-nav .dropdown-item:focus {
+                background: rgba(255, 255, 255, 0.15);
+                color: #fff;
             }
 
             .module-selector-bar {
@@ -777,12 +957,12 @@
                     {% endif %}
                     {% if 'username' in session %}
                     {% if current_permissions.pages.get('my_borrowed_items', True) %}
-                    <li class="nav-item" data-nav-fixed="true">
+                    <li class="nav-item">
                         <a class="nav-link quick-link-pill {% if current_path == url_for('my_borrowed_items') %}nav-active{% endif %}" href="{{ url_for('my_borrowed_items') }}">Meine Ausleihen</a>
                     </li>
                     {% endif %}
                     {% if current_permissions.pages.get('tutorial_page', True) %}
-                    <li class="nav-item" data-nav-fixed="true">
+                    <li class="nav-item">
                         <a class="nav-link quick-link-pill {% if current_path == url_for('tutorial_page') %}nav-active{% endif %}" href="{{ url_for('tutorial_page') }}">Tutorial</a>
                     </li>
                     {% endif %}
@@ -792,20 +972,18 @@
                         <a class="nav-link nav-priority-link {% if current_path == url_for('upload_admin') %}nav-active{% endif %}" href="{{ url_for('upload_admin') }}">➕ Hochladen</a>
                     </li>
                     {% endif %}
+                    <li class="nav-item" data-nav-fixed="true">
+                        <button id="themeToggleBtn" class="btn btn-link nav-link px-3" aria-label="Dark Mode umschalten" title="Theme umschalten">
+                            <span class="theme-icon-light" style="display: none;">☀️</span>
+                            <span class="theme-icon-dark" style="display: none;">🌙</span>
+                        </button>
+                    </li>
+
                     <li class="nav-item dropdown ms-lg-auto">
                         <a class="nav-link dropdown-toggle" href="#" id="invMoreDropdown" role="button" data-bs-toggle="dropdown" aria-expanded="false" title="Weitere Optionen">
                             Mehr Optionen
                         </a>
                         <ul class="dropdown-menu dropdown-menu-end" aria-labelledby="invMoreDropdown">
-                            {% if 'username' in session %}
-                            {% if current_permissions.pages.get('my_borrowed_items', True) %}
-                            <li><a class="dropdown-item" href="{{ url_for('my_borrowed_items') }}">Meine Ausleihen</a></li>
-                            {% endif %}
-                            {% if current_permissions.pages.get('tutorial_page', True) %}
-                            <li><a class="dropdown-item" href="{{ url_for('tutorial_page') }}">Tutorial</a></li>
-                            {% endif %}
-                            <li><hr class="dropdown-divider"></li>
-                            {% endif %}
                             {% if 'username' in session and (session.get('admin', False) or is_admin) and current_permissions.actions.get('can_manage_settings', True) %}
                             <li><h6 class="dropdown-header">Verwaltung</h6></li>
                             {% if current_permissions.pages.get('manage_filters', True) %}
@@ -898,12 +1076,12 @@
                     {% endif %}
                     {% if 'username' in session %}
                     {% if current_permissions.pages.get('my_borrowed_items', True) %}
-                    <li class="nav-item" data-nav-fixed="true">
+                    <li class="nav-item">
                         <a class="nav-link quick-link-pill {% if current_path == url_for('my_borrowed_items') %}nav-active{% endif %}" href="{{ url_for('my_borrowed_items') }}">Meine Medien</a>
                     </li>
                     {% endif %}
                     {% if current_permissions.pages.get('tutorial_page', True) %}
-                    <li class="nav-item" data-nav-fixed="true">
+                    <li class="nav-item">
                         <a class="nav-link quick-link-pill {% if current_path == url_for('tutorial_page') %}nav-active{% endif %}" href="{{ url_for('tutorial_page') }}">Tutorial</a>
                     </li>
                     {% endif %}
@@ -913,20 +1091,18 @@
                         <a class="nav-link nav-priority-link {% if current_path == url_for('library_admin') %}nav-active{% endif %}" href="{{ url_for('library_admin') }}">📖 Hochladen</a>
                     </li>
                     {% endif %}
+                    <li class="nav-item" data-nav-fixed="true">
+                        <button id="themeToggleBtn" class="btn btn-link nav-link px-3" aria-label="Dark Mode umschalten" title="Theme umschalten">
+                            <span class="theme-icon-light" style="display: none;">☀️</span>
+                            <span class="theme-icon-dark" style="display: none;">🌙</span>
+                        </button>
+                    </li>
+
                     <li class="nav-item dropdown ms-lg-auto">
                         <a class="nav-link dropdown-toggle" href="#" id="libMoreDropdown" role="button" data-bs-toggle="dropdown" aria-expanded="false" title="Weitere Optionen">
                             Mehr Optionen
                         </a>
                         <ul class="dropdown-menu dropdown-menu-end" aria-labelledby="libMoreDropdown">
-                            {% if 'username' in session %}
-                            {% if current_permissions.pages.get('my_borrowed_items', True) %}
-                            <li><a class="dropdown-item" href="{{ url_for('my_borrowed_items') }}">Meine Medien</a></li>
-                            {% endif %}
-                            {% if current_permissions.pages.get('tutorial_page', True) %}
-                            <li><a class="dropdown-item" href="{{ url_for('tutorial_page') }}">Tutorial</a></li>
-                            {% endif %}
-                            <li><hr class="dropdown-divider"></li>
-                            {% endif %}
                             {% if 'username' in session and (session.get('admin', False) or is_admin) and current_permissions.actions.get('can_manage_settings', True) %}
                             <li><h6 class="dropdown-header">Bibliotheks-Verwaltung</h6></li>
                             {% if current_permissions.pages.get('library_loans_admin', True) %}
@@ -1029,7 +1205,7 @@
 
         #onboarding-modal {
             width: min(680px, 100%);
-            background: #ffffff;
+            background: var(--ui-surface);
             border-radius: 14px;
             border: 1px solid #dbe3ee;
             box-shadow: 0 18px 35px rgba(15, 23, 42, 0.25);
@@ -1504,8 +1680,15 @@
             const libraryNavList = document.getElementById('libraryNavList');
             const libNavOverflowAnchor = document.getElementById('lib-nav-overflow-anchor');
 
-            function initNavbarOverflow(navList, navOverflowAnchor) {
-                if (!navList || !navOverflowAnchor) return;
+            function initNavbarOverflow(navList, navOverflowAnchor, options) {
+                if (!navList) return;
+
+                const moreToggleId = options && options.moreToggleId ? options.moreToggleId : '';
+                const moreToggle = moreToggleId ? document.getElementById(moreToggleId) : null;
+                const moreControlItem = moreToggle ? moreToggle.closest('li.nav-item.dropdown') : null;
+                const moreMenu = moreControlItem ? moreControlItem.querySelector(':scope > ul.dropdown-menu') : null;
+                const moreLabelDefault = moreToggle ? moreToggle.textContent.trim() : 'Mehr Optionen';
+                const moreMenuOriginal = moreMenu ? moreMenu.innerHTML : '';
 
                 const navRoot = navList.closest('nav.navbar');
                 const navCollapse = navList.closest('.navbar-collapse');
@@ -1533,45 +1716,35 @@
                     return Array.from(navList.children).filter(function(li){
                         if (!(li instanceof HTMLElement)) return false;
                         if (!li.classList.contains('nav-item')) return false;
-                        if (li.id === navOverflowAnchor.id) return false;
+                        if (navOverflowAnchor && li.id === navOverflowAnchor.id) return false;
                         if (li.dataset.overflowControl === 'true') return false;
                         if (li.dataset.navFixed === 'true') return false;
+                        if (moreControlItem && li === moreControlItem) return false;
                         return li.style.display !== 'none';
                     });
                 }
 
                 function clearOverflowControls() {
-                    if (!navList) return;
-                    navList.querySelectorAll('[data-overflow-control="true"]').forEach(function(node){
-                        node.remove();
-                    });
+                    if (!moreMenu) return;
+                    moreMenu.innerHTML = moreMenuOriginal;
+                    if (moreControlItem) {
+                        moreControlItem.style.display = '';
+                    }
+                    if (moreToggle) {
+                        moreToggle.textContent = moreLabelDefault;
+                    }
                 }
 
                 function restoreAllNavItems() {
                     if (!navList) return;
                     navList.querySelectorAll('li.nav-item').forEach(function(li){
-                        if (li.id === navOverflowAnchor.id) return;
+                        if (navOverflowAnchor && li.id === navOverflowAnchor.id) return;
                         if (li.dataset.overflowControl === 'true') return;
                         li.style.display = '';
                     });
                     clearOverflowControls();
                 }
 
-                function createOverflowControl() {
-                    const li = document.createElement('li');
-                    li.className = 'nav-item dropdown';
-                    li.dataset.overflowControl = 'true';
-
-                    const toggleId = navOverflowAnchor.id + '-toggle';
-                    const menuId = navOverflowAnchor.id + '-menu';
-
-                    li.innerHTML =
-                        '<a class="nav-link dropdown-toggle" href="#" id="' + toggleId + '" role="button" data-bs-toggle="dropdown" aria-expanded="false" aria-controls="' + menuId + '">⋮ Weitere</a>' +
-                        '<ul class="dropdown-menu" aria-labelledby="' + toggleId + '" id="' + menuId + '"></ul>';
-
-                    return li;
-                }
-
                 function getNavCandidatePriority(item) {
                     if (!(item instanceof HTMLElement)) {
                         return -1;
@@ -1654,33 +1827,70 @@
 
                 function rebuildOverflowControl(hiddenSources) {
                     clearOverflowControls();
-                    if (!navList || !navOverflowAnchor || hiddenSources.length === 0) return;
-
-                    const control = createOverflowControl();
-                    const menu = control.querySelector('ul.dropdown-menu');
-                    const controlLink = control.querySelector(':scope > a.nav-link');
-                    if (controlLink) {
-                        controlLink.textContent = '⋮ Weitere (' + hiddenSources.length + ')';
-                    }
+                    if (!moreMenu || hiddenSources.length === 0) return;
 
+                    const overflowFragment = document.createDocumentFragment();
                     hiddenSources.forEach(function(source){
-                        appendSourceToOverflowMenu(source, menu);
+                        appendSourceToOverflowMenu(source, overflowFragment);
                     });
 
-                    const trailingDivider = menu.querySelector('li:last-child .dropdown-divider');
-                    if (trailingDivider) {
+                    const overflowWrap = document.createElement('div');
+                    overflowWrap.appendChild(overflowFragment);
+                    const trailingDivider = overflowWrap.querySelector('li:last-child .dropdown-divider');
+                    if (trailingDivider && trailingDivider.parentElement) {
                         trailingDivider.parentElement.remove();
                     }
 
-                    navList.insertBefore(control, navOverflowAnchor);
+                    const overflowEntries = Array.from(overflowWrap.childNodes);
+                    if (overflowEntries.length > 0) {
+                        const marker = document.createElement('li');
+                        marker.innerHTML = '<h6 class="dropdown-header">Ausgeblendete Navigation</h6>';
+                        const firstExistingNode = moreMenu.firstChild;
+                        moreMenu.insertBefore(marker, firstExistingNode);
+
+                        let insertAfter = marker;
+                        overflowEntries.forEach(function(node){
+                            moreMenu.insertBefore(node, insertAfter.nextSibling);
+                            insertAfter = node;
+                        });
+
+                        const divider = document.createElement('li');
+                        divider.innerHTML = '<hr class="dropdown-divider">';
+                        moreMenu.insertBefore(divider, insertAfter.nextSibling);
+
+                        if (moreToggle) {
+                            moreToggle.textContent = moreLabelDefault + ' (' + hiddenSources.length + ')';
+                        }
+                    }
+
+                    if (moreControlItem) {
+                        moreControlItem.style.display = '';
+                    }
                 }
 
                 function adaptNavbarByWidth() {
-                    if (!navList || !navOverflowAnchor) return;
+                    if (!navList) return;
+
+                    const isMobileViewport = window.matchMedia('(max-width: 991.98px)').matches;
+
+                    function isNavOverflowing(bufferPx) {
+                        const buffer = typeof bufferPx === 'number' ? bufferPx : 0;
+                        const collapseOverflow = navCollapse ? (navCollapse.scrollWidth > (navCollapse.clientWidth - buffer)) : false;
+                        const containerOverflow = navContainer ? (navContainer.scrollWidth > (navContainer.clientWidth - buffer)) : false;
+                        const listOverflow = navList.scrollWidth > (navList.clientWidth - buffer);
+                        return collapseOverflow || containerOverflow || listOverflow;
+                    }
 
                     applyCompactMode();
 
-                    if (window.innerWidth < 992) {
+                    // Desktop/tablet-large: keep complete navigation visible.
+                    if (!isMobileViewport) {
+                        restoreAllNavItems();
+                        return;
+                    }
+
+                    // Mobile menu is collapsed: avoid hiding links preemptively.
+                    if (navCollapse && !navCollapse.classList.contains('show')) {
                         restoreAllNavItems();
                         return;
                     }
@@ -1689,8 +1899,9 @@
 
                     const hiddenSources = [];
                     let candidates = collectTopLevelNavSources();
+                    const overflowBuffer = 12;
 
-                    while (navList.scrollWidth > navList.clientWidth && candidates.length > 0) {
+                    while (isNavOverflowing(overflowBuffer) && candidates.length > 0) {
                         const toHide = pickNextNavItemToHide(candidates);
                         if (!toHide) {
                             break;
@@ -1702,8 +1913,9 @@
 
                     rebuildOverflowControl(hiddenSources);
 
+                    // One final pass in case the overflow menu label/count itself changed row width.
                     candidates = collectTopLevelNavSources();
-                    while (navList.scrollWidth > navList.clientWidth && candidates.length > 0) {
+                    while (isNavOverflowing(overflowBuffer) && candidates.length > 0) {
                         const toHide = pickNextNavItemToHide(candidates);
                         if (!toHide) {
                             break;
@@ -1741,12 +1953,12 @@
 
             // Initialize overflow control for inventory navbar
             if (navList && navOverflowAnchor) {
-                initNavbarOverflow(navList, navOverflowAnchor);
+                initNavbarOverflow(navList, navOverflowAnchor, { moreToggleId: 'invMoreDropdown' });
             }
 
             // Initialize overflow control for library navbar
             if (libraryNavList && libNavOverflowAnchor) {
-                initNavbarOverflow(libraryNavList, libNavOverflowAnchor);
+                initNavbarOverflow(libraryNavList, libNavOverflowAnchor, { moreToggleId: 'libMoreDropdown' });
             }
         })();
     </script>
@@ -1756,5 +1968,37 @@
     
     <!-- Push Notifications Script -->
     <script src="{{ url_for('static', filename='js/push-notifications.js') }}"></script>
+
+    <!-- Theme Toggle Script -->
+    <script>
+        document.addEventListener('DOMContentLoaded', () => {
+            const toggleBtns = document.querySelectorAll('#themeToggleBtn');
+            if (toggleBtns.length === 0) return;
+            
+            function updateIcons(theme) {
+                const isDark = theme === 'dark';
+                document.querySelectorAll('.theme-icon-light').forEach(icon => icon.style.display = isDark ? 'inline' : 'none');
+                document.querySelectorAll('.theme-icon-dark').forEach(icon => icon.style.display = isDark ? 'none' : 'inline');
+            }
+
+            // Get current setup from initial script in head
+            let currentTheme = document.documentElement.getAttribute('data-theme') || 'light';
+            updateIcons(currentTheme);
+
+            toggleBtns.forEach(btn => {
+                btn.addEventListener('click', (e) => {
+                    e.preventDefault();
+                    currentTheme = currentTheme === 'light' ? 'dark' : 'light';
+                    
+                    document.documentElement.setAttribute('data-theme', currentTheme);
+                    localStorage.setItem('inventarsystem-theme', currentTheme);
+                    document.getElementById('meta-theme-color').setAttribute('content', currentTheme === 'dark' ? '#1a252f' : '#2c3e50');
+                    
+                    updateIcons(currentTheme);
+                });
+            });
+        });
+    </script>
+
 </body>
 </html>

Web/templates/change_password.html

@@ -53,7 +53,7 @@
         max-width: 500px;
         margin: 50px auto;
         padding: 30px;
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
         border-radius: 8px;
         box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
     }

Web/templates/library.html

@@ -208,12 +208,23 @@
 <script>
 // View mode persistence
 const LIBRARY_VIEW_MODE_KEY = 'inventarLibraryViewMode';
+const MOBILE_LIBRARY_MAX_WIDTH = 900;
+const MOBILE_LIBRARY_MIN_ITEMS = 24;
+
+function isMobileViewport() {
+    return window.matchMedia(`(max-width: ${MOBILE_LIBRARY_MAX_WIDTH}px)`).matches;
+}
 
 function setViewMode(mode) {
     localStorage.setItem(LIBRARY_VIEW_MODE_KEY, mode);
     const container = document.getElementById('itemsContainer');
     const tableHeader = document.getElementById('tableHeader');
-    const items = container.querySelectorAll('.item-card');
+    const renderedItems = Array.from(container.querySelectorAll('.item-card'));
+    const virtualizationState = window.mobileLibraryVirtualizationState || null;
+    const detachedItems = virtualizationState && virtualizationState.active && Array.isArray(virtualizationState.items)
+        ? virtualizationState.items.filter(item => !container.contains(item))
+        : [];
+    const items = [...renderedItems, ...detachedItems.filter(item => !container.contains(item))];
     
     items.forEach(item => {
         const cardContent = item.querySelector('.item-content.card-mode');
@@ -236,6 +247,229 @@ function setViewMode(mode) {
     document.getElementById('viewModeToggle').classList.toggle('open', mode === 'table');
 }
 
+function initMobileWindowedLibraryLoading() {
+    const container = document.getElementById('itemsContainer');
+    if (!container) {
+        return;
+    }
+
+    if (!window.mobileLibraryVirtualizationState) {
+        window.mobileLibraryVirtualizationState = {
+            active: false,
+            items: [],
+            topSpacer: null,
+            bottomSpacer: null,
+            averageItemHeight: Math.max(Math.round(window.innerHeight * 0.35), 230),
+            lastStart: -1,
+            lastEnd: -1,
+            framePending: false,
+            scrollListener: null,
+            resizeListener: null,
+            initialized: false
+        };
+    }
+    const state = window.mobileLibraryVirtualizationState;
+
+    function restoreAllImages() {
+        state.items.forEach(item => {
+            const image = item.querySelector('img.item-image');
+            if (!image) {
+                return;
+            }
+
+            const originalSrc = image.dataset.mobileSrc || '';
+            if (!image.getAttribute('src') && originalSrc) {
+                image.setAttribute('src', originalSrc);
+            }
+        });
+    }
+
+    function updateImageMemory(startIndex, endIndex) {
+        const imageBuffer = 4;
+        state.items.forEach((item, index) => {
+            const image = item.querySelector('img.item-image');
+            if (!image) {
+                return;
+            }
+
+            if (!image.dataset.mobileSrc) {
+                image.dataset.mobileSrc = image.getAttribute('src') || '';
+            }
+            image.loading = 'lazy';
+            image.decoding = 'async';
+
+            const shouldKeepLoaded = index >= startIndex - imageBuffer && index < endIndex + imageBuffer;
+            if (shouldKeepLoaded) {
+                if (!image.getAttribute('src') && image.dataset.mobileSrc) {
+                    image.setAttribute('src', image.dataset.mobileSrc);
+                }
+                return;
+            }
+
+            if (image.getAttribute('src')) {
+                image.removeAttribute('src');
+            }
+        });
+    }
+
+    function renderVisibleWindow() {
+        if (!state.active || !state.topSpacer || !state.bottomSpacer) {
+            return;
+        }
+
+        const viewportHeight = window.innerHeight || 800;
+        const scrollTop = window.scrollY || window.pageYOffset || 0;
+        const renderBuffer = viewportHeight * 1.5;
+
+        let startIndex = Math.max(0, Math.floor((scrollTop - renderBuffer) / state.averageItemHeight));
+        let endIndex = Math.min(state.items.length, Math.ceil((scrollTop + viewportHeight + renderBuffer) / state.averageItemHeight));
+
+        if (endIndex - startIndex < 14) {
+            endIndex = Math.min(state.items.length, startIndex + 14);
+        }
+
+        if (startIndex === state.lastStart && endIndex === state.lastEnd) {
+            return;
+        }
+
+        state.lastStart = startIndex;
+        state.lastEnd = endIndex;
+
+        while (state.topSpacer.nextSibling && state.topSpacer.nextSibling !== state.bottomSpacer) {
+            state.topSpacer.nextSibling.remove();
+        }
+
+        const fragment = document.createDocumentFragment();
+        for (let index = startIndex; index < endIndex; index += 1) {
+            fragment.appendChild(state.items[index]);
+        }
+        container.insertBefore(fragment, state.bottomSpacer);
+
+        let measuredHeightSum = 0;
+        let measuredCount = 0;
+        for (let index = startIndex; index < endIndex; index += 1) {
+            const height = state.items[index].getBoundingClientRect().height;
+            if (height > 0) {
+                measuredHeightSum += height;
+                measuredCount += 1;
+            }
+        }
+
+        if (measuredCount > 0) {
+            const measuredAverage = measuredHeightSum / measuredCount;
+            state.averageItemHeight = Math.round((state.averageItemHeight * 3 + measuredAverage) / 4);
+        }
+
+        state.topSpacer.style.height = `${Math.max(0, startIndex * state.averageItemHeight)}px`;
+        state.bottomSpacer.style.height = `${Math.max(0, (state.items.length - endIndex) * state.averageItemHeight)}px`;
+        updateImageMemory(startIndex, endIndex);
+    }
+
+    function scheduleWindowRender() {
+        if (!state.active || state.framePending) {
+            return;
+        }
+        state.framePending = true;
+        requestAnimationFrame(() => {
+            state.framePending = false;
+            renderVisibleWindow();
+        });
+    }
+
+    function activateVirtualization() {
+        if (state.active) {
+            return;
+        }
+
+        if (!Array.isArray(state.items) || state.items.length === 0) {
+            state.items = Array.from(container.querySelectorAll('.library-item'));
+        }
+        if (state.items.length <= MOBILE_LIBRARY_MIN_ITEMS) {
+            return;
+        }
+
+        state.topSpacer = document.createElement('div');
+        state.topSpacer.className = 'mobile-window-spacer top';
+        state.bottomSpacer = document.createElement('div');
+        state.bottomSpacer.className = 'mobile-window-spacer bottom';
+
+        state.items.forEach(item => item.remove());
+        container.appendChild(state.topSpacer);
+        container.appendChild(state.bottomSpacer);
+
+        state.lastStart = -1;
+        state.lastEnd = -1;
+        state.framePending = false;
+        state.active = true;
+
+        if (!state.scrollListener) {
+            state.scrollListener = () => scheduleWindowRender();
+            window.addEventListener('scroll', state.scrollListener, { passive: true });
+        }
+
+        scheduleWindowRender();
+    }
+
+    function deactivateVirtualization() {
+        if (!state.active) {
+            if (!Array.isArray(state.items) || state.items.length === 0) {
+                state.items = Array.from(container.querySelectorAll('.library-item'));
+            }
+            return;
+        }
+
+        if (state.scrollListener) {
+            window.removeEventListener('scroll', state.scrollListener);
+            state.scrollListener = null;
+        }
+
+        if (state.topSpacer && state.topSpacer.parentNode === container) {
+            state.topSpacer.remove();
+        }
+        if (state.bottomSpacer && state.bottomSpacer.parentNode === container) {
+            state.bottomSpacer.remove();
+        }
+
+        const fragment = document.createDocumentFragment();
+        state.items.forEach(item => fragment.appendChild(item));
+        container.appendChild(fragment);
+
+        restoreAllImages();
+
+        state.topSpacer = null;
+        state.bottomSpacer = null;
+        state.lastStart = -1;
+        state.lastEnd = -1;
+        state.framePending = false;
+        state.active = false;
+
+        const currentMode = localStorage.getItem(LIBRARY_VIEW_MODE_KEY) || 'card';
+        setViewMode(currentMode);
+    }
+
+    function syncVirtualizationWithViewport() {
+        if (!Array.isArray(state.items) || state.items.length === 0) {
+            state.items = Array.from(container.querySelectorAll('.library-item'));
+        }
+
+        const shouldVirtualize = isMobileViewport() && state.items.length > MOBILE_LIBRARY_MIN_ITEMS;
+        if (shouldVirtualize) {
+            activateVirtualization();
+            scheduleWindowRender();
+        } else {
+            deactivateVirtualization();
+        }
+    }
+
+    if (!state.initialized) {
+        state.resizeListener = () => syncVirtualizationWithViewport();
+        window.addEventListener('resize', state.resizeListener, { passive: true });
+        state.initialized = true;
+    }
+
+    syncVirtualizationWithViewport();
+}
+
 // Initialize view mode
 document.addEventListener('DOMContentLoaded', function() {
     const savedMode = localStorage.getItem(LIBRARY_VIEW_MODE_KEY) || 'card';
@@ -311,6 +545,8 @@ document.addEventListener('DOMContentLoaded', function() {
             if (e.target === this) this.style.display = 'none';
         });
     });
+
+    initMobileWindowedLibraryLoading();
 });
 
 function displayLibraryItemDetail(item) {

Web/templates/library_borrowings_admin.html

@@ -52,7 +52,7 @@
   }
 
   .summary-card {
-    background: #fff;
+    background: var(--ui-surface);
     border: 1px solid #e2e8f0;
     border-radius: 14px;
     padding: 14px 16px;
@@ -85,11 +85,11 @@
     padding: 11px 14px;
     border: 1px solid #d6dde6;
     border-radius: 12px;
-    background: #fff;
+    background: var(--ui-surface);
   }
 
   .panel {
-    background: #fff;
+    background: var(--ui-surface);
     border: 1px solid #e2e8f0;
     border-radius: 18px;
     padding: 18px;
@@ -120,7 +120,7 @@
     text-transform: uppercase;
     letter-spacing: 0.04em;
     color: #64748b;
-    background: #f8fafc;
+    background: var(--ui-surface-soft);
   }
 
   .library-table tr:hover td {
@@ -408,7 +408,7 @@
 </div>
 
 <div id="damage-invoice-modal" style="display:none; position:fixed; inset:0; background:rgba(15,23,42,0.72); z-index:9999; padding:20px; overflow:auto;">
-  <div style="max-width:760px; margin:40px auto; background:#fff; border-radius:12px; padding:24px; box-shadow:0 20px 60px rgba(0,0,0,0.3);">
+  <div style="max-width:760px; margin:40px auto; background: var(--ui-surface); border-radius:12px; padding:24px; box-shadow:0 20px 60px rgba(0,0,0,0.3);">
     <div style="display:flex; justify-content:space-between; align-items:center; gap:12px; margin-bottom:18px;">
       <div>
         <h2 style="margin:0;">Rechnung erstellen</h2>
@@ -421,15 +421,15 @@
       <div style="display:grid; grid-template-columns:repeat(auto-fit, minmax(240px, 1fr)); gap:16px; margin-bottom:16px;">
         <div>
           <label for="damage-invoice-item" style="display:block; font-weight:700; margin-bottom:6px;">Element</label>
-          <input id="damage-invoice-item" type="text" readonly style="width:100%; padding:10px; border:1px solid #ddd; border-radius:6px; background:#f8fafc;">
+          <input id="damage-invoice-item" type="text" readonly style="width:100%; padding:10px; border:1px solid #ddd; border-radius:6px; background: var(--ui-surface-soft);">
         </div>
         <div>
           <label for="damage-invoice-borrower" style="display:block; font-weight:700; margin-bottom:6px;">Schüler</label>
-          <input id="damage-invoice-borrower" type="text" readonly style="width:100%; padding:10px; border:1px solid #ddd; border-radius:6px; background:#f8fafc;">
+          <input id="damage-invoice-borrower" type="text" readonly style="width:100%; padding:10px; border:1px solid #ddd; border-radius:6px; background: var(--ui-surface-soft);">
         </div>
         <div>
           <label for="damage-invoice-code" style="display:block; font-weight:700; margin-bottom:6px;">Element-ID / Code</label>
-          <input id="damage-invoice-code" type="text" readonly style="width:100%; padding:10px; border:1px solid #ddd; border-radius:6px; background:#f8fafc;">
+          <input id="damage-invoice-code" type="text" readonly style="width:100%; padding:10px; border:1px solid #ddd; border-radius:6px; background: var(--ui-surface-soft);">
         </div>
         <div>
           <label for="damage-invoice-amount" style="display:block; font-weight:700; margin-bottom:6px;">Preis</label>

Web/templates/library_item_invoices.html

@@ -40,7 +40,7 @@
   }
 
   .invoice-card {
-    background: #fff;
+    background: var(--ui-surface);
     border: 1px solid #e2e8f0;
     border-radius: 16px;
     padding: 18px;
@@ -65,7 +65,7 @@
     text-transform: uppercase;
     letter-spacing: 0.04em;
     color: #64748b;
-    background: #f8fafc;
+    background: var(--ui-surface-soft);
   }
 
   .invoice-table tr:hover td {

Web/templates/library_table.html

@@ -18,7 +18,7 @@
     .library-header h1 {
         margin: 0 0 5px 0;
         font-size: 2em;
-        color: #333;
+        color: var(--ui-text);
     }
 
     .library-header p {
@@ -48,7 +48,7 @@
 
     /* Scanner panel */
     .library-scan-panel {
-        background: #ffffff;
+        background: var(--ui-surface);
         border: 1px solid #d9dde4;
         border-radius: 8px;
         padding: 14px;
@@ -68,7 +68,7 @@
         border: 1px solid #d0d7e2;
         border-radius: 6px;
         font-size: 14px;
-        background: #fff;
+        background: var(--ui-surface);
     }
 
     .library-scan-status {
@@ -95,7 +95,7 @@
         border: 1px solid #d9dde4;
         border-radius: 8px;
         overflow: hidden;
-        background: #fff;
+        background: var(--ui-surface);
         max-width: 460px;
     }
 
@@ -111,7 +111,7 @@
         border-radius: 6px;
         cursor: pointer;
         font-weight: 500;
-        color: #333;
+        color: var(--ui-text);
         transition: all 0.2s ease;
     }
 
@@ -160,7 +160,7 @@
     .filter-item label {
         font-weight: 600;
         font-size: 0.9em;
-        color: #333;
+        color: var(--ui-text);
         margin-bottom: 6px;
     }
 
@@ -206,7 +206,7 @@
     }
 
     .library-items-table thead {
-        background: #f8f9fa;
+        background: var(--ui-surface-soft);
         border-bottom: 2px solid #ddd;
     }
 
@@ -214,7 +214,7 @@
         padding: 14px 16px;
         text-align: left;
         font-weight: 600;
-        color: #333;
+        color: var(--ui-text);
         font-size: 0.9em;
         text-transform: uppercase;
         letter-spacing: 0.5px;
@@ -228,7 +228,7 @@
     }
 
     .library-items-table tbody tr:hover {
-        background: #f8f9fa;
+        background: var(--ui-surface-soft);
     }
 
     .library-items-table tbody tr:last-child td {
@@ -238,7 +238,7 @@
     /* Table cells */
     .table-title {
         font-weight: 600;
-        color: #333;
+        color: var(--ui-text);
     }
 
     .table-status {
@@ -320,7 +320,7 @@
     }
 
     .modal-content {
-        background-color: #fff;
+        background-color: var(--ui-surface);
         border-radius: 8px;
         padding: 20px;
         max-width: 900px;
@@ -373,7 +373,7 @@
     }
 
     .close:hover {
-        color: #333;
+        color: var(--ui-text);
     }
 
     /* Mobile responsive */
@@ -494,7 +494,7 @@
         </div>
         <div class="filter-buttons">
             <button id="applyFilterBtn" class="button" style="background: #4f46e5; color: white;">Filter anwenden</button>
-            <button id="clearFilterBtn" class="button" style="background: #f0f2f5; color: #333;">Zurücksetzen</button>
+            <button id="clearFilterBtn" class="button" style="background: #f0f2f5; color: var(--ui-text);">Zurücksetzen</button>
         </div>
     </div>
 

Web/templates/license.html

@@ -337,7 +337,7 @@
         color: #0d6efd;
     }
     .license-content {
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
         padding: 20px 30px;
         border-radius: 0 0 5px 5px;
         border: 1px solid #dee2e6;

Web/templates/logs.html

@@ -217,7 +217,7 @@
     h1 {
         text-align: center;
         margin-bottom: 30px;
-        color: #333;
+        color: var(--ui-text);
     }
     
     .filter-controls {

Web/templates/main.html

@@ -6,7 +6,7 @@
 
     /* Calendar styles for detailed view */
     .calendar-wrapper {
-        background: #fff;
+        background: var(--ui-surface);
         border: 1px solid #dbe3ee;
         border-radius: 12px;
         overflow: hidden;
@@ -19,8 +19,8 @@
         align-items: center;
         gap: 12px;
         padding: 12px;
-        border-bottom: 1px solid #e7edf5;
-        background: #f8fafc;
+        border-bottom: 1px solid var(--ui-border);
+        background: var(--ui-surface-soft);
     }
 
     .calendar-header button {
@@ -28,15 +28,15 @@
         height: 34px;
         border: 1px solid #dbe3ee;
         border-radius: 8px;
-        background: #fff;
-        color: #334155;
+        background: var(--ui-surface);
+        color: var(--ui-text);
         font-weight: 700;
         line-height: 1;
         cursor: pointer;
     }
 
     .calendar-header button:hover {
-        background: #f1f5f9;
+        background: var(--ui-bg);
     }
 
     .calendar-header span {
@@ -60,7 +60,7 @@
         align-items: center;
         justify-content: center;
         border-radius: 8px;
-        color: #334155;
+        color: var(--ui-text);
         font-size: 0.95rem;
         font-weight: 600;
         line-height: 1;
@@ -80,7 +80,7 @@
     }
 
     .cal-cell:not(.header):not(.empty):hover {
-        background: #f1f5f9;
+        background: var(--ui-bg);
     }
 
     .cal-cell.empty {
@@ -109,13 +109,13 @@
     }
 
     .cal-cell.selected.has-booking::after {
-        background: #fff;
+        background: var(--ui-surface);
     }
 
     .calendar-day-details {
         border-top: 1px solid #e7edf5;
         padding: 12px;
-        background: #f8fafc;
+        background: var(--ui-surface-soft);
         display: none;
     }
 
@@ -138,7 +138,7 @@
     }
 
     .cal-booking-item {
-        background: #fff;
+        background: var(--ui-surface);
         border: 1px solid #dbe3ee;
         border-left: 3px solid #2563eb;
         border-radius: 10px;
@@ -173,7 +173,7 @@
 
     .cal-booking-period {
         margin-left: 8px;
-        color: #475569;
+        color: var(--ui-text);
         font-size: 0.85rem;
         font-weight: 600;
     }
@@ -225,14 +225,14 @@
 
     .filter-option-group {
         margin-bottom: 12px;
-        border-bottom: 1px solid #eee;
+        border-bottom: 1px solid var(--ui-border);
         padding-bottom: 8px;
     }
 
     .filter-group-header {
         font-weight: bold;
         margin-bottom: 5px;
-        color: #495057;
+        color: var(--ui-text-muted);
         font-size: 0.9rem;
     }
 
@@ -253,7 +253,7 @@
     }
 
     .filter-tag-group {
-        color: #6c757d;
+        color: var(--ui-text-muted);
         font-size: 0.8em;
         font-style: italic;
         margin-right: 2px;
@@ -262,7 +262,7 @@
     .filter-tag-remove {
         background: none;
         border: none;
-        color: #6c757d;
+        color: var(--ui-text-muted);
         margin-left: 5px;
         cursor: pointer;
         font-size: 1rem;
@@ -296,7 +296,7 @@
     #code-search {
         flex: 1;
         padding: 8px;
-        border: 1px solid #ddd;
+        border: 1px solid var(--ui-border);
         border-radius: 4px;
     }
 
@@ -321,7 +321,7 @@
     border: 1px solid #dc3545 !important;
     }
 </style>
-<div class="container">
+<div class="container admin-content-container">
     <!-- Conflict warning banner (populated by JS) -->
     <div id="conflict-banner" style="display:none; background:#fff3cd; border:1px solid #ffc107; border-left:4px solid #fd7e14; color:#856404; padding:12px 16px; border-radius:4px; margin-bottom:16px; position:relative;">
         <strong>⚠ Reservierungskonflikt</strong>
@@ -724,7 +724,9 @@
     // Add this line to define allItems globally
     let allItems = [];
 
-    const MAIN_ITEMS_PAGE_SIZE = 120;
+    // Dynamic page size: scan viewport/screen size to only load the exact amount needed.
+    const isMobileDevice = window.matchMedia('(max-width: 768px)').matches;
+    const MAIN_ITEMS_PAGE_SIZE = isMobileDevice ? 20 : 120;
     let mainItemsNextOffset = 0;
     let mainItemsHasMore = false;
     let mainItemsLoadingMore = false;
@@ -781,10 +783,10 @@
             styles.flexDirection === 'column';
 
         const distanceToEnd = isMobileLayout
-            ? itemsContainer.scrollHeight - (itemsContainer.scrollTop + itemsContainer.clientHeight)
+            ? Math.max(document.body.scrollHeight, document.documentElement.scrollHeight) - (window.scrollY + window.innerHeight)
             : itemsContainer.scrollWidth - (itemsContainer.scrollLeft + itemsContainer.clientWidth);
         const prefetchThreshold = isMobileLayout
-            ? Math.max(220, itemsContainer.clientHeight * 0.9)
+            ? window.innerHeight * 1.5
             : Math.max(260, itemsContainer.clientWidth * 1.4);
         if (distanceToEnd > prefetchThreshold) {
             return;
@@ -902,7 +904,7 @@
                         const filter2More = filter2Array.length > 1 ? ` (+${filter2Array.length - 1} mehr)` : '';
                         const filter3More = filter3Array.length > 1 ? ` (+${filter3Array.length - 1} mehr)` : '';
 
-                        const imagesHtml = item.Images ? item.Images.map((file, index) => {
+                        const imagesHtml = item.Images && item.Images.length > 0 ? item.Images.slice(0, 1).map((file, index) => {
                             // Get file with correct case handling
                             const image = file;
                             
@@ -1003,14 +1005,14 @@
 
                         card.innerHTML = `
                             <div class="card-content" data-item-id="${item._id}">
-                                <h3 class="item-name-cell">${item.Name}</h3>
-                                <p class="item-ort-cell"><strong>Ort:</strong> ${item.Ort || '-'}</p>
-                                <p class="item-filter1-cell"><strong>Unterrichtsfach:</strong> ${filter1Display}${filter1More}</p>
-                                <p class="item-filter2-cell"><strong>Jahrgangsstufe:</strong> ${filter2Display}${filter2More}</p>
-                                <p class="item-filter3-cell"><strong>Thema:</strong> ${filter3Display}${filter3More}</p>
-                                <p class="item-code-cell"><strong>Barcode:</strong> ${item.Code_4 || '-'}</p>
-                                <p class="item-count-cell"><strong>Anzahl:</strong> ${groupedCount}</p>
-                                ${isGroupedItem ? `<p class="item-count-cell"><strong>Verfügbar:</strong> ${availableGroupedCount}</p>` : ''}
+                                <h3 class="item-col-name">${item.Name}</h3>
+                                <p class="item-col-location"><strong>Ort:</strong> ${item.Ort || '-'}</p>
+                                <p class="item-col-filter1"><strong>Unterrichtsfach:</strong> ${filter1Display}${filter1More}</p>
+                                <p class="item-col-filter2"><strong>Jahrgangsstufe:</strong> ${filter2Display}${filter2More}</p>
+                                <p class="item-col-filter3"><strong>Thema:</strong> ${filter3Display}${filter3More}</p>
+                                <p class="item-col-code"><strong>Barcode:</strong> ${item.Code_4 || '-'}</p>
+                                <p class="item-col-count"><strong>Anzahl:</strong> ${groupedCount}</p>
+                                ${isGroupedItem ? `<p class="item-col-count"><strong>Verfügbar:</strong> ${availableGroupedCount}</p>` : ''}
                                 <div class="image-container">
                                     ${imagesHtml}
                                 </div>
@@ -1167,6 +1169,7 @@
 
         if (!mainItemsScrollPrefetchBound) {
             itemsContainer.addEventListener('scroll', maybePrefetchMainItems, { passive: true });
+            window.addEventListener('scroll', maybePrefetchMainItems, { passive: true });
             mainItemsScrollPrefetchBound = true;
         }
 
@@ -1188,7 +1191,7 @@
                 updateMainItemsLoadingIndicator();
             });
         }, {
-            root: itemsContainer,
+            root: isMobileLayout ? null : itemsContainer,
             threshold: 0.15,
             rootMargin: isMobileLayout ? '0px 0px 900px 0px' : '0px 900px 0px 0px'
         });
@@ -1466,7 +1469,7 @@
                 const badgeText = entry.type === 'repair' ? 'Repariert' : 'Schaden';
                 const metaLine = entry.meta ? `<div style="font-size:0.84rem;color:#4b5563;">${escapeHtml(entry.meta)}</div>` : '';
                 return `
-                    <div style="border:1px solid #dbe3ee;border-radius:8px;padding:10px;background:#fff;display:grid;gap:6px;">
+                    <div style="border:1px solid var(--ui-border);border-radius:8px;padding:10px;background:var(--ui-surface);display:grid;gap:6px;">
                         <div style="display:flex;flex-wrap:wrap;gap:8px;align-items:center;">
                             <span style="display:inline-block;padding:2px 8px;border-radius:999px;font-size:0.75rem;font-weight:700;${badgeStyle}">${badgeText}</span>
                             <span style="font-size:0.84rem;color:#475569;">${entry.dateLabel}</span>
@@ -1628,7 +1631,7 @@
                 
                 <div class="detail-group">
                     <div class="detail-label">Anschaffungskosten:</div>
-                    <div class="detail-value">${item.Anschaffungskosten || '-'}</div>
+                    <div class="detail-value">${item.Anschaffungskosten ? item.Anschaffungskosten + ' €' : '-'}</div>
                 </div>
                 
                 <div class="detail-group full-width">
@@ -1643,7 +1646,7 @@
                             <span>🛠️</span>
                             <span id="toggle-damage-history-text">Historie anzeigen</span>
                         </button>
-                        <div id="damage-history-panel" style="display:none; margin-top:8px; border:1px solid #e7edf5; border-radius:10px; padding:12px; background:#f8fafc;">
+                        <div id="damage-history-panel" style="display:none; margin-top:8px; border:1px solid #e7edf5; border-radius:10px; padding:12px; background: var(--ui-surface-soft);">
                             <div style="display:grid; gap:10px;">${damageHistoryHtml}</div>
                         </div>
                     </div>
@@ -1716,7 +1719,7 @@
                     : `<button class="ausleihen disabled-button" disabled>${item.BlockedNow ? 'Reserviert' : 'Ausgeliehen'}</button>`
                 }
                 ${canScheduleItem ? `<button class="schedule-button" onclick="openScheduleModal('${item._id}')">Termin planen</button>` : ''}
-                <button type="button" class="close-modal secondary-close" onclick="document.getElementById('item-modal').style.display='none';">Schließen</button>
+                <button type="button" class="details-button" onclick="document.getElementById('item-modal').style.display='none';">Schließen</button>
             </div>
         `;
         
@@ -2805,7 +2808,7 @@
     }
 
     .container {
-        background-color: #fff;
+        background-color: var(--ui-surface);
         padding: 20px;
         border-radius: 5px;
         box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
@@ -2830,8 +2833,8 @@
     .filter-group {
         position: relative;
         min-width: 200px;
-        background-color: #fff;
-        border: 1px solid #ddd;
+        background-color: var(--ui-surface);
+        border: 1px solid var(--ui-border);
         border-radius: 5px;
         padding: 10px;
     }
@@ -2844,7 +2847,7 @@
     }
 
     .filter-toggle, .clear-filter {
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
         border: 1px solid #dee2e6;
         border-radius: 3px;
         padding: 3px 8px;
@@ -2853,7 +2856,7 @@
 
     .clear-filter {
         font-size: 0.8rem;
-        color: #6c757d;
+        color: var(--ui-text-muted);
     }
 
     .filter-dropdown {
@@ -2865,7 +2868,7 @@
         max-height: 300px;
         overflow-y: auto;
         background-color: white;
-        border: 1px solid #ddd;
+        border: 1px solid var(--ui-border);
         border-radius: 5px;
         box-shadow: 0 4px 8px rgba(0,0,0,0.2);
         z-index: 100;
@@ -2900,14 +2903,14 @@
 
     .filter-option-group {
         margin-bottom: 12px;
-        border-bottom: 1px solid #eee;
+        border-bottom: 1px solid var(--ui-border);
         padding-bottom: 8px;
     }
 
     .filter-group-header {
         font-weight: bold;
         margin-bottom: 5px;
-        color: #495057;
+        color: var(--ui-text-muted);
         font-size: 0.9rem;
     }
 
@@ -2928,7 +2931,7 @@
     }
 
     .filter-tag-group {
-        color: #6c757d;
+        color: var(--ui-text-muted);
         font-size: 0.8em;
         font-style: italic;
         margin-right: 2px;
@@ -2937,7 +2940,7 @@
     .filter-tag-remove {
         background: none;
         border: none;
-        color: #6c757d;
+        color: var(--ui-text-muted);
         margin-left: 5px;
         cursor: pointer;
         font-size: 1rem;
@@ -2954,7 +2957,7 @@
     #code-search {
         flex: 1;
         padding: 8px;
-        border: 1px solid #ddd;
+        border: 1px solid var(--ui-border);
         border-radius: 4px;
     }
 
@@ -3025,8 +3028,8 @@
         margin-right: 8px;
         border: 1px solid #dbe3ee;
         border-radius: 10px;
-        background: #f8fafc;
-        color: #334155;
+        background: var(--ui-surface-soft);
+        color: var(--ui-text);
         justify-content: center;
         align-items: center;
         flex-direction: column;
@@ -3083,19 +3086,19 @@
     }
 
     .item-card {
-        background-color: #fff;
-        border: 1px solid #ddd;
-        border-radius: 5px;
-        box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
+        background-color: var(--ui-surface);
+        border: 1px solid var(--ui-border);
+        border-radius: var(--ui-radius);
+        box-shadow: var(--ui-shadow-sm);
         padding: 20px;
-        max-width: 300px;
-        flex-shrink: 0;
+        width: 100%;
+        max-width: 340px;
+        flex: 1 1 300px;
         scroll-snap-align: center;
         cursor: pointer;
-        transition: transform 0.2s;
-    position: relative;
+        transition: transform 0.2s, box-shadow 0.2s;
+        position: relative;
     }
-
     .item-card:hover {
         transform: translateY(-5px);
         box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
@@ -3140,7 +3143,7 @@
     .item-modal {
         display: none;
         position: fixed;
-        z-index: 1000;
+        z-index: 2500;
         left: 0;
         top: 0;
         width: 100%;
@@ -3191,7 +3194,7 @@
     .form-group textarea {
         width: 100%;
         padding: 8px;
-        border: 1px solid #ddd;
+        border: 1px solid var(--ui-border);
         border-radius: 4px;
         box-sizing: border-box;
     }
@@ -3235,7 +3238,7 @@
     }
 
     .cancel-button {
-        background-color: #6c757d;
+        background-color: var(--ui-text-muted);
         color: white;
     }
 
@@ -3467,6 +3470,19 @@
     
     /* Responsive adjustments */
     @media (max-width: 768px) {
+        /* Mobile viewport and scrolling improvements */
+        html, body {
+            overflow-x: hidden !important;
+            -webkit-overflow-scrolling: touch !important;
+            touch-action: pan-y !important;
+            height: 100% !important;
+        }
+        
+        body {
+            padding: 0 !important;
+            margin: 0 !important;
+        }
+
         .filter-container {
             flex-direction: column;
         }
@@ -3552,8 +3568,9 @@
             display: grid !important;
             grid-template-columns: 1fr !important;
             gap: 15px !important;
-            padding: 10px 0 0 !important;
+            padding: 10px 0 !important;
             overflow-x: visible !important;
+            scroll-snap-type: none !important;
         }
         
         .item-card {
@@ -3561,6 +3578,9 @@
             margin: 0 !important;
             padding: 15px !important;
             scroll-snap-align: none !important;
+            /* Only render when user looks at it (content-visibility virtualizes the DOM) */
+            content-visibility: auto;
+            contain-intrinsic-size: auto 300px;
         }
         
         .item-card:hover {
@@ -3634,7 +3654,7 @@
             display: block !important;
             margin-bottom: 8px !important;
             font-weight: 600 !important;
-            color: #333 !important;
+            color: var(--ui-title) !important;
         }
         
         .form-group input, .form-group select, .form-group textarea {
@@ -3705,8 +3725,8 @@
     }
 
     /* Element text colors for better visibility */
-    .edit-button, .duplicate-button, .generate-qr-button, .ausleihen {
-        color: black !important;
+    .edit-button, .duplicate-button, .generate-qr-button {
+        color: var(--ui-title) !important;
     }
     
     /* Standardized button styles across the application */
@@ -3839,7 +3859,7 @@
         max-height: 400px;
         overflow: hidden;
         border-radius: 8px;
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
     }
 
     /* Borrower and appointment info panels in modal */
@@ -3867,11 +3887,11 @@
     .modal-details { margin: 20px 0; }
     .detail-group { display: flex; margin-bottom: 10px; align-items: flex-start; }
     .detail-group.full-width { flex-direction: column; margin-bottom: 15px; }
-    .detail-label { font-weight: bold; color: #495057; min-width: 150px; margin-right: 10px; }
+    .detail-label { font-weight: bold; color: var(--ui-text-muted); min-width: 150px; margin-right: 10px; }
     .detail-value { color: #212529; flex: 1; word-wrap: break-word; }
     .detail-group.full-width .detail-label { margin-bottom: 5px; }
     .detail-group.full-width .detail-value {
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
         padding: 10px;
         border-radius: 4px;
         border: 1px solid #dee2e6;
@@ -3935,7 +3955,7 @@
 
     /* Calendar Styles - Optimized & Mobile Friendly */
     .calendar-wrapper {
-        background: #fff;
+        background: var(--ui-surface);
         border-radius: 12px;
         overflow: hidden;
         border: 1px solid #e5e7eb;
@@ -3948,8 +3968,8 @@
         justify-content: space-between;
         align-items: center;
         padding: 15px;
-        background-color: #fff;
-        border-bottom: 1px solid #f3f4f6;
+        background-color: var(--ui-surface);
+        border-bottom: 1px solid var(--ui-border);
     }
     
     .calendar-header button {
@@ -3973,7 +3993,7 @@
     .calendar-grid {
         display: grid;
         grid-template-columns: repeat(7, 1fr);
-        background-color: #fff;
+        background-color: var(--ui-surface);
         padding: 10px;
         gap: 5px;
     }
@@ -4035,7 +4055,7 @@
     }
     
     .cal-cell.selected.has-booking::after {
-        background-color: #fff;
+        background-color: var(--ui-surface);
     }
 
     .calendar-day-details {
@@ -4063,7 +4083,7 @@
     
     .cal-booking-item {
         padding: 10px;
-        background: #fff;
+        background: var(--ui-surface);
         border: 1px solid #e5e7eb;
         border-radius: 8px;
         margin-bottom: 8px;
@@ -4094,6 +4114,7 @@
             border: none !important;
             border-radius: 0 !important;
             box-shadow: none !important;
+            box-sizing: border-box !important;
         }
 
         .filter-group {
@@ -4115,7 +4136,7 @@
             font-size: 0.95rem !important;
             font-weight: 600 !important;
             line-height: 1.35 !important;
-            color: #212529 !important;
+            color: var(--ui-title) !important;
             word-break: break-word !important;
             overflow-wrap: anywhere !important;
         }
@@ -4153,7 +4174,7 @@
             overflow-wrap: break-word !important;
         }
 
-        body.table-view .item-card .card-content .item-name-cell {
+        body.table-view .item-card .card-content .item-col-name {
             font-size: 0.95rem !important;
         }
 
@@ -4193,7 +4214,7 @@
                 display: block !important;
                 margin-right: 0 !important;
                 margin-bottom: 2px !important;
-                color: #6c757d !important;
+                color: var(--ui-text-muted) !important;
                 font-size: 0.8rem !important;
             }
 
@@ -4213,8 +4234,12 @@
         }
 
         .items-container {
-            padding: 6px 0 !important;
-            gap: 10px !important;
+            display: grid !important;
+            grid-template-columns: 1fr !important;
+            gap: 15px !important;
+            padding: 10px 0 !important;
+            overflow-x: visible !important;
+            scroll-snap-type: none !important;
         }
 
         body.table-view .table-view-header {
@@ -4231,16 +4256,17 @@
         }
 
         .item-card {
-            border: none !important;
-            border-radius: 0 !important;
-            box-shadow: none !important;
-            border-bottom: 1px solid #e5e7eb !important;
-            padding: 12px 0 !important;
+            max-width: 100% !important;
+            margin: 0 !important;
+            padding: 15px !important;
+            scroll-snap-align: none !important;
+            content-visibility: auto;
+            contain-intrinsic-size: auto 300px;
         }
 
         .item-card:hover {
-            transform: none !important;
-            box-shadow: none !important;
+            transform: translateY(-2px) !important;
+            box-shadow: var(--ui-shadow-md) !important;
         }
 
         .item-card .image-container {
@@ -4305,13 +4331,12 @@
         }
 
         .modal-content {
-            width: 100% !important;
-            max-width: 100% !important;
-            height: 100vh !important;
-            max-height: 100vh !important;
-            margin: 0 !important;
-            border: none !important;
-            border-radius: 0 !important;
+            width: calc(100vw - 16px) !important;
+            max-width: none !important;
+            margin: 80px auto 10px !important;
+            max-height: 85vh !important;
+            overflow-y: auto !important;
+            border-radius: 8px !important;
             padding: 16px !important;
         }
 
@@ -4430,7 +4455,7 @@ function openItemQuick(id){
 }
 
 .filter-group {
-    background: #ffffff;
+    background: var(--ui-surface);
     border: 1px solid #cfd8e3;
     border-radius: 12px;
     padding: 12px;
@@ -4478,7 +4503,7 @@ function openItemQuick(id){
 }
 
 .clear-filter {
-    background: #fff;
+    background: var(--ui-surface);
     color: #495868;
 }
 
@@ -4487,7 +4512,7 @@ function openItemQuick(id){
     border: 1px solid #cfd8e3;
     border-radius: 12px;
     box-shadow: 0 8px 20px rgba(20, 35, 60, 0.12);
-    background: #ffffff;
+    background: var(--ui-surface);
     padding: 10px;
 }
 
@@ -4573,4 +4598,74 @@ function openItemQuick(id){
     }
 }
 </style>
-{% endblock %}
+{% endblock %}
+<style>
+    /* Admin/Main Content Container align */
+    .admin-content-container {
+        --table-columns: minmax(190px, 2fr) repeat(6, minmax(110px, 1fr));
+    }
+    @media screen and (min-width: 769px) and (max-width: 1024px) {
+        .admin-content-container {
+            width: 90% !important;
+        }
+        .items-container {
+            display: grid !important;
+            grid-template-columns: repeat(2, 1fr) !important;
+            gap: 20px !important;
+        }
+    }
+    @media screen and (max-width: 768px) {
+        .admin-content-container {
+            width: 100% !important;
+            max-width: 100% !important;
+            margin: 0 !important;
+            padding: 12px 12px 18px !important;
+            box-sizing: border-box !important;
+            overflow-x: hidden !important;
+        }
+        .item-card .item-image {
+            width: 100% !important;
+            height: auto !important;
+            max-height: 300px !important;
+            display: block !important;
+            object-fit: cover !important;
+        }
+        .item-card .image-container {
+            height: 200px !important;
+            overflow: hidden !important;
+            position: relative !important;
+            margin-bottom: 15px !important;
+        }
+        .actions {
+            gap: 8px !important;
+            border-top: none !important;
+            padding-top: 8px !important;
+            flex-direction: column !important;
+            align-items: stretch !important;
+        }
+        .actions form,
+        .actions button,
+        .actions a {
+            width: 100% !important;
+        }
+        .items-container, .item-card, .image-container, .item-image {
+            touch-action: pan-y !important;
+            -webkit-overflow-scrolling: touch !important;
+        }
+    }
+    @media (max-width: 767px) {
+        body {
+            overflow-x: hidden;
+            -webkit-overflow-scrolling: touch;
+            touch-action: pan-y;
+        }
+        .admin-content-container {
+            width: 100%;
+            max-width: 100%;
+            margin: 0;
+            padding: 12px 12px 18px;
+            box-sizing: border-box;
+            overflow-x: hidden;
+        }
+    }
+</style>

Web/templates/main_admin.html

@@ -21,7 +21,7 @@
     .items-indicator {
         text-align: center;
         font-size: 0.9rem;
-        color: #495057;
+        color: var(--ui-text-muted);
         margin: 6px 0 16px;
         font-weight: 600;
     }
@@ -55,7 +55,7 @@
         max-width: 980px;
         margin: 0 auto 18px;
         border: 1px solid #dbe3ee;
-        background: #ffffff;
+        background: var(--ui-surface);
         border-radius: 10px;
         padding: 14px;
         box-shadow: 0 8px 18px rgba(15, 23, 42, 0.08);
@@ -78,7 +78,7 @@
     }
 
     .bulk-delete-summary {
-        color: #334155;
+        color: var(--ui-text);
         font-size: 0.92rem;
         margin-top: 4px;
     }
@@ -104,8 +104,8 @@
         border-radius: 8px;
         padding: 9px 12px;
         cursor: pointer;
-        background: #f8fafc;
-        color: #1e293b;
+        background: var(--ui-surface-soft);
+        color: var(--ui-title);
         font-weight: 600;
         text-align: center;
     }
@@ -138,8 +138,8 @@
     .filter-group {
         position: relative;
         min-width: 200px;
-        background-color: #fff;
-        border: 1px solid #ddd;
+        background-color: var(--ui-surface);
+        border: 1px solid var(--ui-border);
         border-radius: 5px;
         padding: 10px;
     }
@@ -152,7 +152,7 @@
     }
 
     .filter-toggle, .clear-filter {
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
         border: 1px solid #dee2e6;
         border-radius: 3px;
         padding: 3px 8px;
@@ -161,7 +161,7 @@
 
     .clear-filter {
         font-size: 0.8rem;
-        color: #6c757d;
+        color: var(--ui-text-muted);
     }
 
     .filter-dropdown {
@@ -173,7 +173,7 @@
         max-height: 300px;
         overflow-y: auto;
         background-color: white;
-        border: 1px solid #ddd;
+        border: 1px solid var(--ui-border);
         border-radius: 5px;
         box-shadow: 0 4px 8px rgba(0,0,0,0.2);
         z-index: 100;
@@ -208,14 +208,14 @@
 
     .filter-option-group {
         margin-bottom: 12px;
-        border-bottom: 1px solid #eee;
+        border-bottom: 1px solid var(--ui-border);
         padding-bottom: 8px;
     }
 
     .filter-group-header {
         font-weight: bold;
         margin-bottom: 5px;
-        color: #495057;
+        color: var(--ui-text-muted);
         font-size: 0.9rem;
     }
 
@@ -236,7 +236,7 @@
     }
 
     .filter-tag-group {
-        color: #6c757d;
+        color: var(--ui-text-muted);
         font-size: 0.8em;
         font-style: italic;
         margin-right: 2px;
@@ -245,7 +245,7 @@
     .filter-tag-remove {
         background: none;
         border: none;
-        color: #6c757d;
+        color: var(--ui-text-muted);
         margin-left: 5px;
         cursor: pointer;
         font-size: 1rem;
@@ -262,7 +262,7 @@
     #code-search {
         flex: 1;
         padding: 8px;
-        border: 1px solid #ddd;
+        border: 1px solid var(--ui-border);
         border-radius: 4px;
     }
 
@@ -333,8 +333,8 @@
         margin-right: 8px;
         border: 1px solid #dbe3ee;
         border-radius: 10px;
-        background: #f8fafc;
-        color: #334155;
+        background: var(--ui-surface-soft);
+        color: var(--ui-text);
         justify-content: center;
         align-items: center;
         flex-direction: column;
@@ -391,16 +391,17 @@
     }
 
     .item-card {
-        background-color: #fff;
-        border: 1px solid #ddd;
-        border-radius: 5px;
-        box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
+        background-color: var(--ui-surface);
+        border: 1px solid var(--ui-border);
+        border-radius: var(--ui-radius);
+        box-shadow: var(--ui-shadow-sm);
         padding: 20px;
-        max-width: 300px;
-        flex-shrink: 0;
+        width: 100%;
+        max-width: 340px;
+        flex: 1 1 300px;
         scroll-snap-align: center;
         cursor: pointer;
-        transition: transform 0.2s;
+        transition: transform 0.2s, box-shadow 0.2s;
         position: relative;
     }
 
@@ -447,7 +448,7 @@
         align-items: center;
         gap: 6px;
         font-size: 0.9rem;
-        color: #475569;
+        color: var(--ui-text);
         cursor: pointer;
         user-select: none;
     }
@@ -581,7 +582,7 @@
     .item-modal {
         display: none;
         position: fixed;
-        z-index: 1000;
+        z-index: 2500;
         left: 0;
         top: 0;
         width: 100%;
@@ -632,7 +633,7 @@
     .form-group textarea {
         width: 100%;
         padding: 8px;
-        border: 1px solid #ddd;
+        border: 1px solid var(--ui-border);
         border-radius: 4px;
         box-sizing: border-box;
     }
@@ -676,7 +677,7 @@
     }
 
     .cancel-button {
-        background-color: #6c757d;
+        background-color: var(--ui-text-muted);
         color: white;
     }
 
@@ -703,15 +704,15 @@
     .filter-inputs {
         margin: 20px 0;
         padding: 15px;
-        border: 1px solid #ddd;
+        border: 1px solid var(--ui-border);
         border-radius: 5px;
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
     }
 
     .filter-inputs h3 {
         margin-top: 0;
         margin-bottom: 15px;
-        color: #495057;
+        color: var(--ui-text-muted);
     }
 
     .multi-filter {
@@ -723,7 +724,7 @@
     .filter-dropdown-select {
         width: 100%;
         padding: 8px;
-        border: 1px solid #ddd;
+        border: 1px solid var(--ui-border);
         border-radius: 4px;
         background-color: white;
     }
@@ -1000,16 +1001,16 @@
 
     /* Disabled Button */
     .disabled-button {
-        background-color: #6c757d !important;
-        border-color: #6c757d !important;
+        background-color: var(--ui-text-muted) !important;
+        border-color: var(--ui-text-muted) !important;
         color: #fff !important;
         cursor: not-allowed !important;
         opacity: 0.6;
     }
 
     .disabled-button:hover {
-        background-color: #6c757d !important;
-        border-color: #6c757d !important;
+        background-color: var(--ui-text-muted) !important;
+        border-color: var(--ui-text-muted) !important;
         transform: none !important;
         box-shadow: none !important;
     }
@@ -1032,7 +1033,7 @@
 
     .detail-label {
         font-weight: bold;
-        color: #495057;
+        color: var(--ui-text-muted);
         min-width: 150px;
         margin-right: 10px;
     }
@@ -1048,7 +1049,7 @@
     }
 
     .detail-group.full-width .detail-value {
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
         padding: 10px;
         border-radius: 4px;
         border: 1px solid #dee2e6;
@@ -1068,7 +1069,7 @@
         max-height: 400px;
         overflow: hidden;
         border-radius: 8px;
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
     }
 
     .modal-image {
@@ -1351,7 +1352,7 @@
             display: block !important;
             margin-bottom: 8px !important;
             font-weight: 600 !important;
-            color: #333 !important;
+            color: var(--ui-title) !important;
         }
         
         .form-group input, .form-group select, .form-group textarea {
@@ -1389,7 +1390,7 @@
         /* Tab navigation improvements */
         .nav-tabs {
             flex-wrap: wrap !important;
-            border-bottom: 1px solid #dee2e6 !important;
+            border-bottom: 1px solid var(--ui-border) !important;
         }
         
         .nav-tabs .nav-link {
@@ -1605,6 +1606,7 @@
             gap: 15px !important;
             padding: 10px 0 !important;
             overflow-x: visible !important;
+            scroll-snap-type: none !important;
         }
         
         .item-card {
@@ -1612,6 +1614,9 @@
             margin: 0 !important;
             padding: 15px !important;
             scroll-snap-align: none !important;
+            /* Only render when user looks at it (content-visibility virtualizes the DOM) */
+            content-visibility: auto;
+            contain-intrinsic-size: auto 300px;
         }
         
         .item-card:hover {
@@ -1685,7 +1690,7 @@
             display: block !important;
             margin-bottom: 8px !important;
             font-weight: 600 !important;
-            color: #333 !important;
+            color: var(--ui-title) !important;
         }
         
         .form-group input, .form-group select, .form-group textarea {
@@ -1959,8 +1964,8 @@
     }
 
     /* Element text colors for better visibility */
-    .edit-button, .duplicate-button, .generate-qr-button, .ausleihen {
-        color: black !important;
+    .edit-button, .duplicate-button, .generate-qr-button {
+        color: var(--ui-title) !important;
     }
     
     /* Standardized button styles across the application */
@@ -2003,7 +2008,7 @@
     }
     /* Calendar styles for detailed view */
     .calendar-wrapper {
-        background: #fff;
+        background: var(--ui-surface);
         border: 1px solid #dbe3ee;
         border-radius: 12px;
         overflow: hidden;
@@ -2016,8 +2021,8 @@
         align-items: center;
         gap: 12px;
         padding: 12px;
-        border-bottom: 1px solid #e7edf5;
-        background: #f8fafc;
+        border-bottom: 1px solid var(--ui-border);
+        background: var(--ui-surface-soft);
     }
 
     .calendar-header button {
@@ -2025,15 +2030,15 @@
         height: 34px;
         border: 1px solid #dbe3ee;
         border-radius: 8px;
-        background: #fff;
-        color: #334155;
+        background: var(--ui-surface);
+        color: var(--ui-text);
         font-weight: 700;
         line-height: 1;
         cursor: pointer;
     }
 
     .calendar-header button:hover {
-        background: #f1f5f9;
+        background: var(--ui-bg);
     }
 
     .calendar-header span {
@@ -2057,7 +2062,7 @@
         align-items: center;
         justify-content: center;
         border-radius: 8px;
-        color: #334155;
+        color: var(--ui-text);
         font-size: 0.95rem;
         font-weight: 600;
         line-height: 1;
@@ -2077,7 +2082,7 @@
     }
 
     .cal-cell:not(.header):not(.empty):hover {
-        background: #f1f5f9;
+        background: var(--ui-bg);
     }
 
     .cal-cell.empty {
@@ -2106,13 +2111,13 @@
     }
 
     .cal-cell.selected.has-booking::after {
-        background: #fff;
+        background: var(--ui-surface);
     }
 
     .calendar-day-details {
         border-top: 1px solid #e7edf5;
         padding: 12px;
-        background: #f8fafc;
+        background: var(--ui-surface-soft);
         display: none;
     }
 
@@ -2135,7 +2140,7 @@
     }
 
     .cal-booking-item {
-        background: #fff;
+        background: var(--ui-surface);
         border: 1px solid #dbe3ee;
         border-left: 3px solid #2563eb;
         border-radius: 10px;
@@ -2170,7 +2175,7 @@
 
     .cal-booking-period {
         margin-left: 8px;
-        color: #475569;
+        color: var(--ui-text);
         font-size: 0.85rem;
         font-weight: 600;
     }
@@ -2579,7 +2584,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
                     <input type="date" id="edit-year" name="anschaffungsjahr">
                 </div>
                 <div class="form-group">
-                    <label for="edit-cost">Anschaffungskosten:</label>
+                    <label for="edit-cost">Anschaffungskosten (€):</label>
                     <input id="edit-cost" name="anschaffungskosten">
                 </div>
                 <div class="form-group">
@@ -3339,7 +3344,9 @@ document.addEventListener('DOMContentLoaded', ()=>{
     });
 
     // Function to load items from server
-    const MAIN_ADMIN_ITEMS_PAGE_SIZE = 120;
+    // Dynamic page size: scan viewport/screen size to only load the exact amount needed.
+    const isMobileDevice = window.matchMedia('(max-width: 768px)').matches;
+    const MAIN_ADMIN_ITEMS_PAGE_SIZE = isMobileDevice ? 20 : 120;
     let mainAdminItemsNextOffset = 0;
     let mainAdminItemsHasMore = false;
     let mainAdminItemsLoadingMore = false;
@@ -3397,10 +3404,10 @@ document.addEventListener('DOMContentLoaded', ()=>{
             styles.flexDirection === 'column';
 
         const distanceToEnd = isMobileLayout
-            ? itemsContainer.scrollHeight - (itemsContainer.scrollTop + itemsContainer.clientHeight)
+            ? Math.max(document.body.scrollHeight, document.documentElement.scrollHeight) - (window.scrollY + window.innerHeight)
             : itemsContainer.scrollWidth - (itemsContainer.scrollLeft + itemsContainer.clientWidth);
         const prefetchThreshold = isMobileLayout
-            ? Math.max(220, itemsContainer.clientHeight * 0.9)
+            ? window.innerHeight * 1.5
             : Math.max(260, itemsContainer.clientWidth * 1.4);
         if (distanceToEnd > prefetchThreshold) {
             return;
@@ -3523,7 +3530,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
                         const filter2More = filter2Array.length > 1 ? ` (+${filter2Array.length - 1} mehr)` : '';
                         const filter3More = filter3Array.length > 1 ? ` (+${filter3Array.length - 1} mehr)` : '';
 
-                        const imagesHtml = item.Images ? item.Images.map((image, index) => {
+                        const imagesHtml = item.Images && item.Images.length > 0 ? item.Images.slice(0, 1).map((image, index) => {
                             // Check if the image already has a full URL path or just the filename
                             const imageSrc = image.startsWith('/uploads/') || image.startsWith('http') ? 
                                             image : 
@@ -3772,6 +3779,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
 
         if (!mainAdminItemsScrollPrefetchBound) {
             itemsContainer.addEventListener('scroll', maybePrefetchMainAdminItems, { passive: true });
+            window.addEventListener('scroll', maybePrefetchMainAdminItems, { passive: true });
             mainAdminItemsScrollPrefetchBound = true;
         }
 
@@ -3793,7 +3801,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
                 updateMainAdminItemsLoadingIndicator();
             });
         }, {
-            root: itemsContainer,
+            root: isMobileLayout ? null : itemsContainer,
             threshold: 0.15,
             rootMargin: isMobileLayout ? '0px 0px 900px 0px' : '0px 900px 0px 0px'
         });
@@ -4355,7 +4363,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
                 const badgeText = entry.type === 'repair' ? 'Repariert' : 'Schaden';
                 const metaLine = entry.meta ? `<div style="font-size:0.84rem;color:#4b5563;">${escapeHtml(entry.meta)}</div>` : '';
                 return `
-                    <div style="border:1px solid #dbe3ee;border-radius:8px;padding:10px;background:#fff;display:grid;gap:6px;">
+                    <div style="border:1px solid var(--ui-border);border-radius:8px;padding:10px;background:var(--ui-surface);display:grid;gap:6px;">
                         <div style="display:flex;flex-wrap:wrap;gap:8px;align-items:center;">
                             <span style="display:inline-block;padding:2px 8px;border-radius:999px;font-size:0.75rem;font-weight:700;${badgeStyle}">${badgeText}</span>
                             <span style="font-size:0.84rem;color:#475569;">${entry.dateLabel}</span>
@@ -4433,7 +4441,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
                 
                 <div class="detail-group">
                     <div class="detail-label">Anschaffungskosten:</div>
-                    <div class="detail-value">${item.Anschaffungskosten || '-'}</div>
+                    <div class="detail-value">${item.Anschaffungskosten ? item.Anschaffungskosten + ' €' : '-'}</div>
                 </div>
                 
                 <div class="detail-group full-width">
@@ -4448,7 +4456,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
                             <span>🛠️</span>
                             <span id="toggle-damage-history-text">Historie anzeigen</span>
                         </button>
-                        <div id="damage-history-panel" style="display:none; margin-top:8px; border:1px solid #e7edf5; border-radius:10px; padding:12px; background:#f8fafc;">
+                        <div id="damage-history-panel" style="display:none; margin-top:8px; border:1px solid #e7edf5; border-radius:10px; padding:12px; background: var(--ui-surface-soft);">
                             <div style="display:grid; gap:10px;">${damageHistoryHtml}</div>
                         </div>
                     </div>
@@ -4527,6 +4535,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
                 <form method="POST" action="/delete_item/${item._id}" style="display:inline;" onsubmit="return confirm('Sind Sie sicher?')">
                     <button class="delete-button" type="submit">Löschen</button>
                 </form>
+                <button type="button" class="details-button" onclick="document.getElementById('item-modal').style.display='none';">Schließen</button>
             </div>
         `;
         
@@ -5494,7 +5503,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
 }
 
 .filter-group {
-    background: #ffffff;
+    background: var(--ui-surface);
     border: 1px solid #cfd8e3;
     border-radius: 12px;
     padding: 12px;
@@ -5542,7 +5551,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
 }
 
 .clear-filter {
-    background: #fff;
+    background: var(--ui-surface);
     color: #495868;
 }
 
@@ -5551,7 +5560,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
     border: 1px solid #cfd8e3;
     border-radius: 12px;
     box-shadow: 0 8px 20px rgba(20, 35, 60, 0.12);
-    background: #ffffff;
+    background: var(--ui-surface);
     padding: 10px;
 }
 
@@ -5661,7 +5670,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
             display: block !important;
             margin-right: 0 !important;
             margin-bottom: 2px !important;
-            color: #6c757d !important;
+            color: var(--ui-text-muted) !important;
             font-size: 0.8rem !important;
         }
 

Web/templates/manage_locations.html

@@ -78,12 +78,12 @@
         border-radius: 5px;
         box-shadow: 0 2px 5px rgba(0,0,0,0.1);
         margin-bottom: 20px;
-        background-color: #fff;
+        background-color: var(--ui-surface);
         border: 1px solid #e9ecef;
     }
     
     .card-header {
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
         padding: 15px 20px;
         border-bottom: 1px solid #e9ecef;
     }
@@ -170,7 +170,7 @@
         justify-content: space-between;
         align-items: center;
         padding: 10px;
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
         border-radius: 4px;
         border-left: 3px solid #6c757d;
     }

Web/templates/my_borrowed_items.html

@@ -61,7 +61,7 @@
         bottom: 125%;
         left: 50%;
         transform: translateX(-50%);
-        background-color: #333;
+        background-color: var(--ui-text);
         color: white;
         padding: 5px 10px;
         border-radius: 4px;
@@ -405,7 +405,7 @@ document.addEventListener('DOMContentLoaded', function() {
     }
     
     .borrowed-item {
-        background-color: #fff;
+        background-color: var(--ui-surface);
         border: 1px solid #dee2e6;
         border-radius: 8px;
         padding: 20px;
@@ -457,7 +457,7 @@ document.addEventListener('DOMContentLoaded', function() {
     
     .exemplar-details {
         margin-top: 10px;
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
         padding: 10px;
         border-radius: 5px;
         border-left: 3px solid #6c757d;
@@ -515,7 +515,7 @@ document.addEventListener('DOMContentLoaded', function() {
     .no-items-message {
         text-align: center;
         padding: 30px;
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
         border-radius: 5px;
         color: #6c757d;
         margin-top: 20px;

Web/templates/notifications.html

@@ -17,7 +17,7 @@
   <div id="push-notification-settings" style="margin-bottom: 24px;"></div>
 
   <div style="display:grid; grid-template-columns:1fr; gap:14px;">
-    <section style="background:#fff; border:1px solid #e2e8f0; border-radius:14px; padding:16px;">
+    <section style="background: var(--ui-surface); border:1px solid #e2e8f0; border-radius:14px; padding:16px;">
       <h2 style="margin:0 0 12px; font-size:1.15rem;">Meine Benachrichtigungen</h2>
       {% if user_notifications %}
       <div style="display:grid; gap:10px;">
@@ -53,7 +53,7 @@
     </section>
 
     {% if is_admin_user %}
-    <section style="background:#fff; border:1px solid #e2e8f0; border-radius:14px; padding:16px;">
+    <section style="background: var(--ui-surface); border:1px solid #e2e8f0; border-radius:14px; padding:16px;">
       <h2 style="margin:0 0 12px; font-size:1.15rem;">Admin-Benachrichtigungen</h2>
       {% if admin_notifications %}
       <div style="display:grid; gap:10px;">

Web/templates/register.html

@@ -70,27 +70,6 @@
                     </div>
                 </div>
 
-                {% if student_cards_module_enabled %}
-                <div class="form-group">
-                    <label style="display:flex; align-items:center; gap:8px; color:#1f2937;">
-                        <input type="checkbox" id="is-student" name="is_student" style="width:auto;">
-                        Schülerkonto mit Ausweis
-                    </label>
-                    <div id="student-fields" style="display:none; margin-top:10px;">
-                        <label for="student-card-id">Ausweis-ID</label>
-                        <div class="input-container">
-                            <span class="input-icon">🪪</span>
-                            <input type="text" id="student-card-id" name="student_card_id" placeholder="z.B. S-2026-001">
-                        </div>
-                        <label for="max-borrow-days" style="margin-top:10px;">Standard-Ausleihdauer (Tage)</label>
-                        <div class="input-container">
-                            <span class="input-icon">📅</span>
-                            <input type="number" id="max-borrow-days" name="max_borrow_days" min="1" max="{{ student_max_borrow_days }}" value="{{ student_default_borrow_days }}">
-                        </div>
-                    </div>
-                </div>
-                {% endif %}
-
                 <div class="form-group">
                     <label for="permission-preset">Berechtigungs-Preset</label>
                     <select id="permission-preset" name="permission_preset" class="form-select">
@@ -142,7 +121,7 @@
     --primary-dark: #2980b9;
     --success-color: #2ecc71;
     --error-color: #e74c3c;
-    --text-color: #333;
+    --text-color: var(--ui-text);
     --light-bg: #f9f9f9;
     --border-radius: 8px;
     --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
@@ -184,7 +163,7 @@ body {
 }
 
 .content {
-    background-color: #fff;
+    background-color: var(--ui-surface);
     padding: 2rem;
     border-radius: var(--border-radius);
     box-shadow: var(--shadow);
@@ -366,7 +345,7 @@ input::placeholder {
     padding: 10px 12px;
     border: 1px solid #e5e7eb;
     border-radius: 8px;
-    background: #f8fafc;
+    background: var(--ui-surface-soft);
 }
 
 .password-rules-title {
@@ -427,7 +406,7 @@ input::placeholder {
     border: 1px solid #d1d5db;
     border-radius: 8px;
     padding: 10px;
-    background: #f8fafc;
+    background: var(--ui-surface-soft);
 }
 
 .permission-panel h4 {
@@ -561,25 +540,6 @@ document.addEventListener('DOMContentLoaded', function () {
         passwordInput.addEventListener('blur', updatePasswordRules);
         updatePasswordRules();
     }
-
-    {% if student_cards_module_enabled %}
-    const studentCheckbox = document.getElementById('is-student');
-    const studentFields = document.getElementById('student-fields');
-    const studentCardInput = document.getElementById('student-card-id');
-
-    if (!studentCheckbox || !studentFields || !studentCardInput) {
-        return;
-    }
-
-    function toggleStudentFields() {
-        const isChecked = studentCheckbox.checked;
-        studentFields.style.display = isChecked ? 'block' : 'none';
-        studentCardInput.required = isChecked;
-    }
-
-    studentCheckbox.addEventListener('change', toggleStudentFields);
-    toggleStudentFields();
-    {% endif %}
 });
 </script>
 {% endblock %}

Web/templates/reset_item_functions.html

@@ -129,7 +129,7 @@ function createLoadingIndicator(message) {
             }
             
             .reset-loading-message {
-                color: #333;
+                color: var(--ui-text);
                 font-size: 16px;
                 font-weight: 500;
             }

Web/templates/reset_item_modal.html

@@ -207,7 +207,7 @@
 }
 
 .reset-item-info {
-    background: #f8f9fa;
+    background: var(--ui-surface-soft);
     border-radius: 8px;
     padding: 20px;
     margin-bottom: 25px;
@@ -216,7 +216,7 @@
 
 .reset-item-info h3 {
     margin: 0 0 15px 0;
-    color: #333;
+    color: var(--ui-text);
     font-size: 1.3rem;
 }
 
@@ -232,7 +232,7 @@
 }
 
 .reset-item-details strong {
-    color: #333;
+    color: var(--ui-text);
 }
 
 .reset-warning-section {
@@ -285,7 +285,7 @@
     flex-direction: column;
     cursor: pointer;
     font-weight: 500;
-    color: #333;
+    color: var(--ui-text);
 }
 
 .reset-action-desc {
@@ -298,7 +298,7 @@
 .active-borrowings {
     margin-top: 10px;
     padding: 10px;
-    background: #f8f9fa;
+    background: var(--ui-surface-soft);
     border-radius: 5px;
     font-size: 0.9rem;
 }
@@ -321,7 +321,7 @@
 
 .reset-options-section h4 {
     margin: 0 0 15px 0;
-    color: #333;
+    color: var(--ui-text);
 }
 
 .reset-option {
@@ -365,7 +365,7 @@
     display: block;
     margin-bottom: 8px;
     font-weight: 500;
-    color: #333;
+    color: var(--ui-text);
 }
 
 .reset-reason-section textarea {
@@ -391,7 +391,7 @@
     display: flex;
     justify-content: flex-end;
     gap: 15px;
-    background: #f8f9fa;
+    background: var(--ui-surface-soft);
     border-radius: 0 0 12px 12px;
 }
 

Web/templates/student_card_barcode_print.html

@@ -45,7 +45,7 @@
         }
 
         h1 {
-            color: #333;
+            color: var(--ui-text);
             font-size: 28px;
             margin-bottom: 10px;
         }
@@ -67,7 +67,7 @@
         }
 
         .info-box strong {
-            color: #333;
+            color: var(--ui-text);
         }
 
         .info-box p {
@@ -106,7 +106,7 @@
 
         .btn-secondary {
             background: #e0e0e0;
-            color: #333;
+            color: var(--ui-text);
         }
 
         .btn-secondary:hover {

Web/templates/student_cards_admin.html

@@ -22,7 +22,7 @@
     }
 
     .student-card-form {
-        background: #f5f5f5;
+        background: var(--ui-bg);
         padding: 20px;
         border-radius: 8px;
         margin-bottom: 30px;
@@ -43,7 +43,7 @@
     .form-group label {
         font-weight: 600;
         margin-bottom: 5px;
-        color: #333;
+        color: var(--ui-text);
     }
 
     .form-group input,

Web/templates/terminplan.html

@@ -1601,7 +1601,7 @@ document.addEventListener('DOMContentLoaded', function() {
 .booking-summary {
     margin: 15px 0;
     padding: 10px;
-    background-color: #f8f9fa;
+    background-color: var(--ui-surface-soft);
     border: 1px solid #ddd;
     border-radius: 4px;
     font-size: 0.9em;

Web/templates/tutorial.html

@@ -72,7 +72,7 @@
 
   .tutorial-side {
     grid-column: span 12;
-    background: #ffffff;
+    background: var(--ui-surface);
     border: 1px solid #cfdbe8;
     border-radius: 16px;
     padding: 16px;
@@ -102,7 +102,7 @@
 
   .workflow-nav button {
     border: 1px solid #dbe3ee;
-    background: #f8fafc;
+    background: var(--ui-surface-soft);
     color: #0f172a;
     border-radius: 12px;
     padding: 11px 12px;
@@ -133,7 +133,7 @@
 
   .workflow-step {
     grid-column: span 12;
-    background: #ffffff;
+    background: var(--ui-surface);
     border: 1px solid #cfdbe8;
     border-radius: 16px;
     padding: 18px;
@@ -331,17 +331,17 @@
         <h3>Tägliche Aufgaben</h3>
         <p>Das ist der gewöhnliche Arbeitsablauf während eines Schultages.</p>
         
-        <div style="background: #f8fafc; border: 1px solid #dbe3ee; border-radius: 12px; padding: 14px; margin: 14px 0;">
+        <div style="background: var(--ui-surface-soft); border: 1px solid #dbe3ee; border-radius: 12px; padding: 14px; margin: 14px 0;">
           <p style="margin-bottom: 10px; font-weight: 700; color: #0f172a;">Morgens:</p>
           <p style="margin: 0; color: #334155;">Öffnen Sie die Startseite und prüfen Sie offene Reservierungen oder Rückgabefristen.</p>
         </div>
 
-        <div style="background: #f8fafc; border: 1px solid #dbe3ee; border-radius: 12px; padding: 14px; margin: 14px 0;">
+        <div style="background: var(--ui-surface-soft); border: 1px solid #dbe3ee; border-radius: 12px; padding: 14px; margin: 14px 0;">
           <p style="margin-bottom: 10px; font-weight: 700; color: #0f172a;">Mittags:</p>
           <p style="margin: 0; color: #334155;">Neue Artikel oder Bücher hinzufügen oder Ausleihungen begründen.</p>
         </div>
 
-        <div style="background: #f8fafc; border: 1px solid #dbe3ee; border-radius: 12px; padding: 14px; margin: 14px 0;">
+        <div style="background: var(--ui-surface-soft); border: 1px solid #dbe3ee; border-radius: 12px; padding: 14px; margin: 14px 0;">
           <p style="margin-bottom: 10px; font-weight: 700; color: #0f172a;">Nachmittags:</p>
           <p style="margin: 0; color: #334155;">Rückgaben buchen und kurz prüfen, ob alles in Ordnung ist.</p>
         </div>

Web/templates/upload_admin.html

@@ -78,14 +78,14 @@
 
     .book-info {
         padding: 15px;
-        background-color: #fff;
+        background-color: var(--ui-surface);
         border: 1px solid #ddd;
         border-radius: 5px;
         margin-bottom: 10px;
     }
 
     .book-info h4 {
-        color: #333;
+        color: var(--ui-text);
         margin: 0 0 10px 0;
         font-size: 1.2em;
         font-weight: bold;
@@ -115,7 +115,7 @@
     }
 
     .book-description h5 {
-        color: #333;
+        color: var(--ui-text);
         margin: 0 0 8px 0;
         font-size: 1em;
         font-weight: bold;
@@ -125,7 +125,7 @@
         max-height: 150px;
         overflow-y: auto;
         padding: 5px;
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
         border: 1px solid #e9ecef;
         border-radius: 3px;
         font-size: 0.9em;
@@ -187,7 +187,7 @@
         font-style: italic;
         text-align: center;
         padding: 20px;
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
         border: 1px solid #dee2e6;
         border-radius: 4px;
     }
@@ -334,7 +334,7 @@
     }
 
     .popup-content p {
-        color: #333;
+        color: var(--ui-text);
         margin: 15px 0;
         line-height: 1.5;
         font-size: 1em;
@@ -380,7 +380,7 @@
     }
 
     .popup-close-x:hover {
-        color: #333;
+        color: var(--ui-text);
     }
 
     /* Upload form styles */
@@ -388,13 +388,13 @@
         max-width: 800px;
         margin: 0 auto;
         padding: 20px;
-        background-color: #fff;
+        background-color: var(--ui-surface);
         border-radius: 8px;
         box-shadow: 0 2px 10px rgba(0,0,0,0.1);
     }
 
     .upload-form h1 {
-        color: #333;
+        color: var(--ui-text);
         margin-bottom: 30px;
         text-align: center;
         font-size: 2em;
@@ -408,7 +408,7 @@
         display: block;
         margin-bottom: 5px;
         font-weight: bold;
-        color: #333;
+        color: var(--ui-text);
     }
 
     .form-group input,
@@ -428,14 +428,14 @@
     }
 
     .filter-inputs {
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
         padding: 20px;
         border-radius: 5px;
         margin: 20px 0;
     }
 
     .filter-inputs h3 {
-        color: #333;
+        color: var(--ui-text);
         margin-bottom: 15px;
         font-size: 1.2em;
     }
@@ -863,7 +863,7 @@
                 <input type="date" id="anschaffungsjahr" name="anschaffungsjahr">
             </div>
             <div class="form-group">
-                <label for="anschaffungskosten">Anschaffungskosten</label>
+                <label for="anschaffungskosten">Anschaffungskosten (€)</label>
                 <input id="anschaffungskosten" name="anschaffungskosten">
             </div>
             <div class="form-group">

Web/templates/user_del.html

@@ -407,14 +407,14 @@
     }
     
     .filter-bar {
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
         padding: 15px;
         border-radius: 6px;
         border: 1px solid #dee2e6;
     }
 
     .password-requirements {
-        background-color: #f8f9fa;
+        background-color: var(--ui-surface-soft);
         padding: 10px;
         border-radius: 4px;
         margin-top: 10px;
@@ -439,7 +439,7 @@
         border: 1px solid #dee2e6;
         border-radius: 8px;
         padding: 12px;
-        background: #f8fafc;
+        background: var(--ui-surface-soft);
     }
 
     .permissions-group h6 {

Web/tenant.py

@@ -10,11 +10,43 @@ Each tenant can support up to 20+ users with isolated data and resource pools.
 from flask import request, g, has_request_context
 from functools import wraps
 import logging
+import settings as cfg
 
 logger = logging.getLogger(__name__)
 
 # Tenant registry: maps subdomain/tenant_id to database name
 TENANT_REGISTRY = {}
+if isinstance(getattr(cfg, 'TENANT_CONFIGS', None), dict):
+    TENANT_REGISTRY.update(cfg.TENANT_CONFIGS)
+
+
+def _get_nested_value(source, path, default=None):
+    current = source
+    for key in path:
+        if isinstance(current, dict) and key in current:
+            current = current[key]
+        else:
+            return default
+    return current
+
+
+def get_tenant_config(tenant_id=None):
+    """Return the registered config for a tenant, falling back to default."""
+    if tenant_id is None:
+        ctx = get_tenant_context()
+        tenant_id = ctx.tenant_id if ctx and ctx.tenant_id else 'default'
+
+    if tenant_id in TENANT_REGISTRY:
+        return TENANT_REGISTRY[tenant_id] or {}
+
+    return TENANT_REGISTRY.get('default', {}) or {}
+
+
+def is_tenant_module_enabled(module_name, tenant_id=None, default=False):
+    """Resolve whether a feature module is enabled for the current tenant."""
+    config = get_tenant_config(tenant_id)
+    enabled = _get_nested_value(config, ['modules', module_name, 'enabled'], default)
+    return bool(enabled)
 
 
 class TenantContext:
@@ -27,6 +59,7 @@ class TenantContext:
         self.tenant_id = None
         self.db_name = None
         self.subdomain = None
+        self.config = {}
 
     def resolve_tenant(self):
         """
@@ -40,6 +73,7 @@ class TenantContext:
         tenant_from_header = request.headers.get('X-Tenant-ID', '').strip()
         if tenant_from_header:
             self.tenant_id = tenant_from_header
+            self.config = get_tenant_config(tenant_from_header)
             return self._get_db_name(tenant_from_header)
 
         # Priority 2: Subdomain extraction
@@ -56,10 +90,12 @@ class TenantContext:
             if potential_subdomain not in ('www', 'api', 'admin', 'app', 'mail'):
                 self.subdomain = potential_subdomain
                 self.tenant_id = potential_subdomain
+                self.config = get_tenant_config(potential_subdomain)
                 return self._get_db_name(potential_subdomain)
 
         # Fallback to default tenant if no subdomain detected
         self.tenant_id = 'default'
+        self.config = get_tenant_config('default')
         return self._get_db_name('default')
 
     def _get_db_name(self, tenant_id):

backup.sh

@@ -33,11 +33,12 @@ LOG_FILE="${LOG_FILE:-$LOG_DIR/backup.log}"
 COMPRESSION_LEVEL="${COMPRESSION_LEVEL:-9}"
 KEEP_DAYS="${KEEP_DAYS:-7}"
 MIN_KEEP="${MIN_KEEP:-7}"
-DB_NAME="${DB_NAME:-Inventarsystem}"
+DB_NAME="${DB_NAME:-inventar_default}"
 MONGO_URI="${MONGO_URI:-mongodb://localhost:27017/}"
 INVOICE_KEEP_DAYS="${INVOICE_KEEP_DAYS:-3650}"
 INVOICE_ARCHIVE_DIR="${INVOICE_ARCHIVE_DIR:-$BACKUP_BASE_DIR/invoice-archive}"
 BACKUP_MODE="${BACKUP_MODE:-auto}"
+COMPOSE_FILE="${COMPOSE_FILE:-docker-compose-multitenant.yml}"
 DOCKER_AVAILABLE=0
 DOCKER_COMPOSE_CMD=()
 USE_NULL_OUTPUT=false
@@ -58,6 +59,8 @@ Options:
     --keep-days <N>                   Age-based retention in days (default: $KEEP_DAYS; 0 disables age filter)
     --min-keep <N>                    Always keep at least this many backups (default: $MIN_KEEP)
     --mode <auto|host|docker>         Backup mode (default: $BACKUP_MODE)
+    --multitenant                     Use docker-compose-multitenant.yml (default)
+    --singletenant                    Use docker-compose.yml
   -h|--help                         Show this help and exit
 EOF
 }
@@ -87,6 +90,10 @@ while [[ $# -gt 0 ]]; do
             MIN_KEEP="$2"; shift 2;;
         --mode)
             BACKUP_MODE="$2"; shift 2;;
+        --multitenant)
+            COMPOSE_FILE="docker-compose-multitenant.yml"; shift;;
+        --singletenant)
+            COMPOSE_FILE="docker-compose.yml"; shift;;
         -h|--help)
             usage; exit 0;;
         *)
@@ -102,12 +109,12 @@ log_message() {
 init_docker_compose() {
     if docker compose version >/dev/null 2>&1; then
         DOCKER_AVAILABLE=1
-        DOCKER_COMPOSE_CMD=(docker compose -f "$PROJECT_DIR/docker-compose.yml")
+        DOCKER_COMPOSE_CMD=(docker compose -f "$PROJECT_DIR/$COMPOSE_FILE")
         return 0
     fi
     if sudo docker compose version >/dev/null 2>&1; then
         DOCKER_AVAILABLE=1
-        DOCKER_COMPOSE_CMD=(sudo docker compose -f "$PROJECT_DIR/docker-compose.yml")
+        DOCKER_COMPOSE_CMD=(sudo docker compose -f "$PROJECT_DIR/$COMPOSE_FILE")
         return 0
     fi
 

build-nuitka.sh

@@ -1,107 +0,0 @@
-#!/usr/bin/env bash
-set -euo pipefail
-
-SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
-cd "$SCRIPT_DIR"
-
-SUDO=""
-if [ "$(id -u)" -ne 0 ] && command -v sudo >/dev/null 2>&1; then
-    SUDO="sudo"
-fi
-
-VENV_PYTHON="$SCRIPT_DIR/.venv/bin/python"
-if [ ! -x "$VENV_PYTHON" ]; then
-    echo "Error: .venv python not found at $VENV_PYTHON"
-    echo "Create it first, e.g.: python3 -m venv .venv && source .venv/bin/activate && pip install -r requirements.txt"
-    exit 1
-fi
-
-if [ "$(id -u)" -ne 0 ] && [ ! -w "$SCRIPT_DIR/.venv" ]; then
-    echo "Fixing ownership of .venv for current user..."
-    if [ -n "$SUDO" ]; then
-        $SUDO chown -R "$(id -un):$(id -gn)" "$SCRIPT_DIR/.venv"
-    else
-        echo "Error: .venv is not writable and sudo is unavailable."
-        exit 1
-    fi
-fi
-
-for path in "$SCRIPT_DIR/dist" "$SCRIPT_DIR/build"; do
-    if [ -e "$path" ] && [ "$(id -u)" -ne 0 ]; then
-        echo "Ensuring ownership of $(basename "$path") for current user..."
-        if [ -n "$SUDO" ]; then
-            $SUDO chown -R "$(id -un):$(id -gn)" "$path"
-        else
-            if [ ! -w "$path" ]; then
-                echo "Error: $path is not writable and sudo is unavailable."
-                exit 1
-            fi
-        fi
-    fi
-done
-
-echo "Installing Nuitka build dependencies in .venv..."
-"$VENV_PYTHON" -m pip install --upgrade pip setuptools wheel
-"$VENV_PYTHON" -m pip install --upgrade "nuitka==2.8.10" ordered-set zstandard
-
-DIST_DIR="$SCRIPT_DIR/dist"
-BUILD_DIR="$SCRIPT_DIR/build"
-OUTPUT_NAME="inventarsystem"
-
-mkdir -p "$DIST_DIR" "$BUILD_DIR"
-
-NUITKA_DATA_ARGS=()
-
-if [ -d "$SCRIPT_DIR/Web/templates" ]; then
-    NUITKA_DATA_ARGS+=("--include-data-dir=$SCRIPT_DIR/Web/templates=templates")
-fi
-
-if [ -d "$SCRIPT_DIR/Web/static" ]; then
-    NUITKA_DATA_ARGS+=("--include-data-dir=$SCRIPT_DIR/Web/static=static")
-fi
-
-if [ -d "$SCRIPT_DIR/uploads" ]; then
-    NUITKA_DATA_ARGS+=("--include-data-dir=$SCRIPT_DIR/uploads=uploads")
-fi
-
-ORIGINAL_PERF_PARANOID=""
-if [ -r /proc/sys/kernel/perf_event_paranoid ]; then
-    ORIGINAL_PERF_PARANOID="$(cat /proc/sys/kernel/perf_event_paranoid)"
-    if [ "$ORIGINAL_PERF_PARANOID" -gt 1 ]; then
-        echo "Temporarily setting kernel.perf_event_paranoid=1 for Nuitka build compatibility..."
-        if ! $SUDO sh -c 'echo 1 > /proc/sys/kernel/perf_event_paranoid'; then
-            echo "Warning: Could not adjust kernel.perf_event_paranoid automatically."
-            echo "Run: sudo sh -c 'echo 1 > /proc/sys/kernel/perf_event_paranoid' and retry."
-            exit 1
-        fi
-    fi
-fi
-
-restore_perf_setting() {
-    if [ -n "$ORIGINAL_PERF_PARANOID" ] && [ "$ORIGINAL_PERF_PARANOID" -gt 1 ]; then
-        $SUDO sh -c "echo $ORIGINAL_PERF_PARANOID > /proc/sys/kernel/perf_event_paranoid" >/dev/null 2>&1 || true
-    fi
-}
-
-trap restore_perf_setting EXIT
-
-echo "Building standalone binary with Nuitka..."
-"$VENV_PYTHON" -m nuitka \
-    --standalone \
-    --assume-yes-for-downloads \
-    --follow-imports \
-    --output-dir="$DIST_DIR" \
-    --output-filename="$OUTPUT_NAME" \
-    "${NUITKA_DATA_ARGS[@]}" \
-    --remove-output \
-    "$SCRIPT_DIR/Web/app.py"
-
-APP_DIST_DIR="$DIST_DIR/app.dist"
-if [ -d "$APP_DIST_DIR" ]; then
-    echo "Nuitka build complete."
-    echo "Run with: $APP_DIST_DIR/$OUTPUT_NAME"
-else
-    echo "Build finished, but expected output directory not found: $APP_DIST_DIR"
-    echo "Check Nuitka output above."
-    exit 1
-fi

config.json

@@ -1,9 +1,9 @@
 {
     "dbg": false,
     "key": "InventarsystemSecureKey2026XYZ789abcdef012",
-    "ver": "0.0.2",
+    "ver": "0.6.44",
     "host": "0.0.0.0",
-    "port": 443,
+    "port": 8000,
 
     "mongodb": {
         "host": "localhost",
@@ -50,6 +50,8 @@
         }
     },
 
+    "tenants": {},
+
     "allowed_extensions": [
         "png", "jpg", "jpeg", "gif",
         "hevc", "heif",

config.yml

@@ -0,0 +1,13 @@
+tunnel: homeserver
+credentials-file: /etc/cloudflared/credentials.json
+
+ingress:
+  # Repo 1: Inventar
+  - hostname: inventar.maximiliangruendinger.de
+    service: http://inventory-app:3000
+
+  # Repo 2: Key-Service (Buchung)
+  - hostname: booking.maximiliangruendinger.de
+    service: http://key-service-app:8080 
+
+  - service: http_status:404

docker-compose-multitenant.yml

@@ -8,9 +8,35 @@
 # Scale example: To support 10 tenants with 20 users each:
 #   docker-compose -f docker-compose-multitenant.yml up -d --scale app=10
 
-version: '3.9'
-
 services:
+  cloudflared:
+    image: cloudflare/cloudflared:latest
+    container_name: cloudflared
+    restart: unless-stopped
+    profiles:
+      - cloudflare
+    command: ["--config", "/etc/cloudflared/config.yml", "tunnel", "run"]
+    volumes:
+      - ./docker/cloudflared/config.yml:/etc/cloudflared/config.yml:ro
+      - /etc/cloudflared/credentials.json:/etc/cloudflared/credentials.json:ro
+    depends_on:
+      nginx:
+        condition: service_started
+    networks:
+      - inventar-net
+
+  # Management Container for multi-tenant scripts
+  tenant-manager:
+    image: docker:cli
+    container_name: tenant-manager
+    restart: "no"
+    profiles:
+      - tools
+    volumes:
+      - /var/run/docker.sock:/var/run/docker.sock
+      - .:/workspace
+    entrypoint: ["sh", "-c", "cd /workspace && ./manage-tenant.sh \"$$@\"", "--"]
+
   nginx:
     image: nginx:1.27-alpine
     container_name: inventarsystem-nginx
@@ -22,7 +48,7 @@ services:
         condition: service_started
     ports:
       - "${INVENTAR_HTTP_PORT:-80}:80"
-      - "${INVENTAR_HTTPS_PORT:-443}:443"
+      - "${INVENTAR_HTTPS_PORT:-8000}:8000"
     volumes:
       - ./docker/nginx/multitenant.conf:/etc/nginx/conf.d/default.conf:ro
       - ./certs:/etc/nginx/certs:ro
@@ -59,9 +85,8 @@ services:
     image: mongo:7.0
     container_name: inventarsystem-mongodb
     restart: unless-stopped
-    command: mongod --wiredTigerCacheSizeGB 2 --journal --dbPath /data/db
-    ports:
-      - "27017:27017"
+    expose:
+      - "27017"
     volumes:
       - mongodb_data:/data/db
       - ./docker/mongo:/docker-entrypoint-initdb.d:ro
@@ -82,6 +107,8 @@ services:
       args:
         PYTHON_VERSION: "3.13"
         OPTIMIZATION_LEVEL: 2
+    working_dir: /app/Web
+    command: ["gunicorn", "app:app", "--bind", "0.0.0.0:8000", "--workers", "2", "--timeout", "30", "--graceful-timeout", "20", "--max-requests", "200", "--max-requests-jitter", "50", "--log-level", "info", "--access-logfile", "-", "--error-logfile", "-"]
     restart: unless-stopped
     security_opt:
       - no-new-privileges:true
@@ -96,7 +123,6 @@ services:
       - "8000"
     volumes:
       - ./config.json:/app/config.json:ro
-      - ./Web:/app/Web:ro
       - app_uploads:/app/Web/uploads:cached
       - app_thumbnails:/app/Web/thumbnails:cached
       - app_previews:/app/Web/previews:cached
@@ -181,9 +207,6 @@ volumes:
 networks:
   inventar-net:
     driver: bridge
-    ipam:
-      config:
-        - subnet: 172.20.0.0/16
 
 # Scale guidance:
 # 1 tenant (20 users): 1 app instance + redis + mongodb = ~500MB
@@ -196,3 +219,4 @@ networks:
 # - Medium (5-10 tenants): 4GB RAM, 2-4 CPU cores  
 # - Large (10-20 tenants): 8GB RAM, 4-8 CPU cores
 # - Jumbo (20+ tenants): 16GB+ RAM, 8+ CPU cores with clustering
+

docker-compose.yml

@@ -1,87 +1,41 @@
+version: "3.8"
+
 services:
-  nginx:
-    image: nginx:1.27-alpine
-    container_name: inventarsystem-nginx
+  app:
+    build: .
+    container_name: inventory-app
     restart: unless-stopped
+    environment:
+      - MONGO_URL=mongodb://mongodb:27017/inventar
+      - REDIS_URL=redis://redis:6379
+      - BASE_URL=https://inventar.maximiliangruendinger.de #alle öffentliche subdomains
     depends_on:
-      app:
-        condition: service_started
-    ports:
-      - "${INVENTAR_HTTP_PORT:-80}:80"
-      - "${INVENTAR_HTTPS_PORT:-443}:443"
-    volumes:
-      - ./docker/nginx/default.conf:/etc/nginx/conf.d/default.conf:ro
-      - ./certs:/etc/nginx/certs:ro
+      - mongodb
+      - redis
 
   mongodb:
-    image: mongo:7.0
-    container_name: inventarsystem-mongodb
+    image: mongo:latest
+    container_name: mongodb
     restart: unless-stopped
     volumes:
-      - mongodb_data:/data/db
-    healthcheck:
-      test: ["CMD", "mongosh", "--quiet", "--eval", "db.adminCommand('ping').ok"]
-      interval: 10s
-      timeout: 5s
-      retries: 10
+      - mongo_data:/data/db
 
   redis:
-    image: redis:7-alpine
-    container_name: inventarsystem-redis
+    image: redis:alpine
+    container_name: redis
     restart: unless-stopped
-    command: ["redis-server", "--appendonly", "yes", "--save", "60", "1000"]
-    volumes:
-      - redis_data:/data
-    healthcheck:
-      test: ["CMD", "redis-cli", "ping"]
-      interval: 10s
-      timeout: 3s
-      retries: 10
 
-  app:
-    build:
-      context: .
-      dockerfile: Dockerfile
-    container_name: inventarsystem-app
+  cloudflared:
+    image: cloudflare/cloudflared:latest
+    container_name: cloudflared
     restart: unless-stopped
-    security_opt:
-      - no-new-privileges:true
-    depends_on:
-      mongodb:
-        condition: service_healthy
-      redis:
-        condition: service_healthy
-    environment:
-      INVENTAR_MONGODB_HOST: mongodb
-      INVENTAR_MONGODB_PORT: "27017"
-      INVENTAR_MONGODB_DB: Inventarsystem
-      INVENTAR_REDIS_HOST: redis
-      INVENTAR_REDIS_PORT: "6379"
-      INVENTAR_REDIS_CACHE_DB: "1"
-      INVENTAR_NOTIFICATION_STATUS_CACHE_TTL: "8"
-      INVENTAR_BACKUP_FOLDER: /data/backups
-      INVENTAR_LOGS_FOLDER: /data/logs
-      INVENTAR_DELETED_ARCHIVE_FOLDER: /data/deleted-archives
-    expose:
-      - "8000"
+    # Der Tunnel-Name 'homeserver' muss zu deiner credentials.json passen
+    command: tunnel run homeserver
     volumes:
-      - ./config.json:/app/config.json:ro
-      - ./Web:/app/Web:ro
-      - app_uploads:/app/Web/uploads
-      - app_thumbnails:/app/Web/thumbnails
-      - app_previews:/app/Web/previews
-      - app_qrcodes:/app/Web/QRCodes
-      - app_backups:/data/backups
-      - app_logs:/data/logs
-      - app_deleted_archives:/data/deleted-archives
+      - ./config.yml:/etc/cloudflared/config.yml
+      - ./credentials.json:/etc/cloudflared/credentials.json
+    depends_on:
+      - app
 
 volumes:
-  mongodb_data:
-  app_uploads:
-  app_thumbnails:
-  app_previews:
-  app_qrcodes:
-  app_backups:
-  app_logs:
-  app_deleted_archives:
-  redis_data:
+  mongo_data:

docker/cloudflared/config.yml

@@ -0,0 +1,8 @@
+tunnel: homeserver
+credentials-file: /etc/cloudflared/credentials.json
+
+ingress:
+  - service: https://nginx:443
+    originRequest:
+      noTLSVerify: true
+  - service: http_status:404

docker/nginx/multitenant.conf

@@ -37,7 +37,8 @@ upstream inventar_backend {
 
 # Main HTTPS server block
 server {
-    listen 443 ssl http2;
+    listen 443 ssl;
+    http2 on;
     server_name ~^(?<tenant>[a-z0-9-]+)?\.?example\.com$;
 
     # SSL Configuration (wildcard certificate)
@@ -75,9 +76,9 @@ server {
                application/x-javascript application/xml+rss application/json;
     gzip_comp_level 5;
 
-    # Access/Error logs with tenant in filename
-    access_log /var/log/nginx/inventar_access_${tenant}.log combined buffer=32k;
-    error_log /var/log/nginx/inventar_error_${tenant}.log warn;
+    # Access/Error logs
+    access_log /var/log/nginx/inventar_access.log combined buffer=32k;
+    error_log /var/log/nginx/inventar_error.log warn;
 
     # Root location - proxy to app with tenant context
     location / {

flask.pid

@@ -0,0 +1 @@
+394722

install.sh

@@ -22,6 +22,7 @@ LEGACY_BACKUP_ARCHIVE=""
 CLEANUP_OLD_SERVICES=true
 CLEANUP_OLD_REMOVE_CRON=false
 TMP_DIR=""
+COMPOSE_FILE="docker-compose-multitenant.yml"
 
 cleanup_tmp_dir() {
     if [ -n "${TMP_DIR:-}" ] && [ -d "$TMP_DIR" ]; then
@@ -50,14 +51,13 @@ refresh_start_script_from_main() {
 pin_compose_app_image() {
     local tag="$1"
     local compose_file
-    compose_file="$PROJECT_DIR/docker-compose.yml"
 
-    if [ ! -f "$compose_file" ]; then
-        echo "Warning: $compose_file not found; cannot pin app image"
-        return 0
-    fi
+    for compose_file in "$PROJECT_DIR/docker-compose-multitenant.yml" "$PROJECT_DIR/docker-compose.yml"; do
+        if [ ! -f "$compose_file" ]; then
+            continue
+        fi
 
-    python3 - <<'PY' "$compose_file" "$tag"
+        python3 - <<'PY' "$compose_file" "$tag"
 import re
 import sys
 
@@ -151,6 +151,8 @@ if in_app_service and build_found and app_service_indent is not None:
 with open(compose_file, "w", encoding="utf-8") as f:
     f.writelines(out)
 PY
+
+    done
 }
 
 install_docker_if_missing() {
@@ -173,6 +175,8 @@ Options:
   --remove-legacy-system        Remove old host MongoDB/system after successful import
     --skip-cleanup-old            Do not run cleanup-old.sh after install
     --cleanup-old-remove-cron     Also remove matching cron entries during old-system cleanup
+    --multitenant                Use docker-compose-multitenant.yml (default)
+    --singletenant               Use docker-compose.yml
   --legacy-db-name <name>       Legacy database name (default: $LEGACY_DB_NAME)
   --legacy-mongo-uri <uri>      Legacy Mongo URI (default: $LEGACY_MONGO_URI)
   --legacy-system-dir <path>    Optional old system directory to remove after migration
@@ -199,6 +203,14 @@ parse_args() {
                 CLEANUP_OLD_REMOVE_CRON=true
                 shift
                 ;;
+            --multitenant)
+                COMPOSE_FILE="docker-compose-multitenant.yml"
+                shift
+                ;;
+            --singletenant)
+                COMPOSE_FILE="docker-compose.yml"
+                shift
+                ;;
             --legacy-db-name)
                 LEGACY_DB_NAME="$2"
                 shift 2
@@ -280,14 +292,21 @@ backup_legacy_database() {
 
 restore_legacy_backup_into_docker() {
     local i
+    local compose_path
 
     if [ "$MIGRATE_LEGACY_DB" != "true" ] || [ -z "$LEGACY_BACKUP_ARCHIVE" ]; then
         return 0
     fi
 
+    compose_path="$PROJECT_DIR/$COMPOSE_FILE"
+    if [ ! -f "$compose_path" ]; then
+        echo "Error: compose file not found: $compose_path"
+        exit 1
+    fi
+
     echo "Waiting for Docker MongoDB to become ready..."
     for i in $(seq 1 60); do
-        if sudo docker compose -f "$PROJECT_DIR/docker-compose.yml" exec -T mongodb mongosh --quiet --eval "db.adminCommand({ping:1}).ok" >/dev/null 2>&1; then
+        if sudo docker compose -f "$compose_path" exec -T mongodb mongosh --quiet --eval "db.adminCommand({ping:1}).ok" >/dev/null 2>&1; then
             break
         fi
         sleep 2
@@ -299,7 +318,7 @@ restore_legacy_backup_into_docker() {
     fi
 
     echo "Importing legacy backup into Docker MongoDB..."
-    sudo docker compose -f "$PROJECT_DIR/docker-compose.yml" exec -T mongodb mongorestore --archive --gzip --drop --nsInclude "${LEGACY_DB_NAME}.*" < "$LEGACY_BACKUP_ARCHIVE"
+    sudo docker compose -f "$compose_path" exec -T mongodb mongorestore --archive --gzip --drop --nsInclude "${LEGACY_DB_NAME}.*" < "$LEGACY_BACKUP_ARCHIVE"
     echo "Legacy DB import completed."
 }
 

manage-tenant.sh

@@ -0,0 +1,143 @@
+#!/bin/sh
+# Script to manage multitenant deployment
+# Allows adding, removing, and restarting tenants without downtime for others
+
+if [ ! -f "docker-compose-multitenant.yml" ]; then
+    echo "Error: docker-compose-multitenant.yml not found."
+    exit 1
+fi
+
+show_help() {
+    echo "Usage: ./manage-tenant.sh [COMMAND] [OPTIONS]"
+    echo ""
+    echo "Commands:"
+    echo "  add <tenant_id>       Add a new tenant (initializes database)"
+    echo "  remove <tenant_id>    Remove a tenant completely (deletes data!)"
+    echo "  restart-tenant <id>   'Restart' a single tenant (clears cache/sessions)"
+    echo "  restart-all           Restart all application containers (zero-downtime reload)"
+    echo "  list                  List active tenants"
+    echo ""
+    echo "Examples:"
+    echo "  ./manage-tenant.sh add school_a"
+    echo "  ./manage-tenant.sh remove test_tenant"
+    echo "  ./manage-tenant.sh restart-all"
+    exit 1
+}
+
+if [ -z "$1" ]; then
+    show_help
+fi
+
+COMMAND=$1
+TENANT_ID=$2
+
+case "$COMMAND" in
+    add)
+        if [ -z "$TENANT_ID" ]; then
+            echo "Error: Please provide a tenant_id."
+            exit 1
+        fi
+        echo "Adding new tenant '$TENANT_ID'..."
+        # Add Nginx configuration
+        if [ -f "docker/nginx/multitenant.conf" ]; then
+            echo "Assuming dynamic routing based on subdomain ($TENANT_ID)..."
+        fi
+        
+        # Initialize tenant database via Python inside container
+        echo "Initializing database for $TENANT_ID..."
+        APP_CONTAINER=$(docker ps -qf "name=app" | head -n 1)
+        if [ -n "$APP_CONTAINER" ]; then
+            docker exec $APP_CONTAINER python3 -c "
+import sys; sys.path.insert(0, '/app/Web'); import settings; from pymongo import MongoClient; import hashlib
+client = MongoClient(settings.MONGODB_HOST, int(settings.MONGODB_PORT))
+db = client[f'{settings.MONGODB_DB}_{sys.argv[1]}']
+hashed_pw = hashlib.sha512('admin123'.encode()).hexdigest()
+db.users.insert_one({'Username': 'admin', 'Password': hashed_pw, 'Role': 'admin', 'Name': 'Admin', 'Nachname': 'User'})
+print(f'Tenant {sys.argv[1]} database initialized. Default admin: admin / admin123')
+" "$TENANT_ID"
+            echo "Tenant '$TENANT_ID' successfully added. Ready to use."
+        else
+            echo "Warning: Application container is not running. Please start the multi-tenant system first."
+            echo "Data will be initialized upon first access by the tenant."
+        fi
+        ;;
+    
+    remove)
+        if [ -z "$TENANT_ID" ]; then
+            echo "Error: Please provide a tenant_id to remove."
+            exit 1
+        fi
+        echo -n "WARNING: Are you sure you want to permanently delete all data for tenant '$TENANT_ID'? (y/N) "
+        read confirm
+        if [ "$confirm" = "y" ] || [ "$confirm" = "Y" ]; then
+            echo "Removing tenant '$TENANT_ID'..."
+            APP_CONTAINER=$(docker ps -qf "name=app" | head -n 1)
+            if [ -n "$APP_CONTAINER" ]; then
+                docker exec $APP_CONTAINER python3 -c "
+import sys; sys.path.insert(0, '/app/Web'); import settings; from pymongo import MongoClient
+client = MongoClient(settings.MONGODB_HOST, int(settings.MONGODB_PORT))
+client.drop_database(f'{settings.MONGODB_DB}_{sys.argv[1]}')
+print(f'Database for tenant {sys.argv[1]} dropped.')
+" "$TENANT_ID"
+                echo "Tenant '$TENANT_ID' removed successfully."
+            else
+                echo "Error: Application container not running."
+            fi
+        else
+            echo "Removal canceled."
+        fi
+        ;;
+
+    restart-tenant)
+        if [ -z "$TENANT_ID" ]; then
+            echo "Error: Please provide a tenant_id."
+            exit 1
+        fi
+        echo "Restarting tenant '$TENANT_ID' (clearing session/cache)..."
+        # To restart a single tenant without restarting the global python processes,
+        # we can invalidate their cache or drop their sessions collection to sign everyone out
+        APP_CONTAINER=$(docker ps -qf "name=app" | head -n 1)
+        if [ -n "$APP_CONTAINER" ]; then
+            docker exec $APP_CONTAINER python3 -c "
+import sys; sys.path.insert(0, '/app/Web'); import settings; from pymongo import MongoClient
+client = MongoClient(settings.MONGODB_HOST, int(settings.MONGODB_PORT))
+db = client[f'{settings.MONGODB_DB}_{sys.argv[1]}']
+db.sessions.drop() # Force sign-out / session clear
+print(f'Tenant {sys.argv[1]} session cache cleared. Tenant restarted.')
+" "$TENANT_ID"
+            echo "Tenant '$TENANT_ID' has been refreshed without impacting others."
+        else
+             echo "Error: Application container not running."
+        fi
+        ;;
+
+    restart-all)
+        echo "Restarting all application instances with zero-downtime rolling restart..."
+        docker restart $(docker ps -qf "name=app")
+        echo "Global restart complete."
+        ;;
+        
+    list)
+        echo "Listing active tenants (Databases):"
+        APP_CONTAINER=$(docker ps -qf "name=app" | head -n 1)
+        if [ -n "$APP_CONTAINER" ]; then
+             docker exec $APP_CONTAINER python3 -c "
+import sys; sys.path.insert(0, '/app/Web'); import settings; from pymongo import MongoClient
+client = MongoClient(settings.MONGODB_HOST, int(settings.MONGODB_PORT))
+prefix = f'{settings.MONGODB_DB}_'
+dbs = [d for d in client.list_database_names() if d.startswith(prefix)]
+for db in dbs:
+    print(f'- {db.replace(prefix, \"\")}')
+"
+        else
+            echo "Error: Application container not running."
+        fi
+        ;;
+
+    *)
+        echo "Unknown command: $COMMAND"
+        show_help
+        ;;
+esac
+
+exit 0

requirements.txt

@@ -14,3 +14,4 @@ python-barcode
 openpyxl
 cryptography
 pywebpush
+py-vapid==1.9.0

restart.sh

@@ -1,7 +1,14 @@
 #!/bin/bash
+
+# Nur die App neu bauen und starten, ohne den Tunnel oder die DB zu killen
+docker compose up -d --build app
+
+# Optional: Alles aufräumen, was nicht mehr gebraucht wird
+docker image prune -f
+
 set -euo pipefail
 
 SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
 
-"$SCRIPT_DIR/stop.sh"
-"$SCRIPT_DIR/start.sh"
+"$SCRIPT_DIR/stop.sh" "$@"
+"$SCRIPT_DIR/start.sh" "$@"

restore.sh

@@ -6,12 +6,13 @@ LOG_DIR="$SCRIPT_DIR/logs"
 LOG_FILE="$LOG_DIR/restore.log"
 WORK_DIR="$(mktemp -d /tmp/inventarsystem-restore-XXXXXX)"
 
-DB_NAME="${INVENTAR_MONGODB_DB:-Inventarsystem}"
+DB_NAME="${INVENTAR_MONGODB_DB:-inventar_default}"
 SOURCE_PATH=""
 BACKUP_DATE=""
 DROP_DATABASE=false
 RESTART_SERVICES=false
 STAGED_PATH=""
+COMPOSE_FILE="docker-compose-multitenant.yml"
 
 BACKUP_ROOT_LOCAL="$SCRIPT_DIR/backups"
 BACKUP_ROOT_SYSTEM="/var/backups"
@@ -56,6 +57,8 @@ Options:
                           - latest: newest from local/system backup roots
   --drop-database         Drop target DB before import (recommended for full restore)
   --restart-services      Restart stack after restore
+    --multitenant           Use docker-compose-multitenant.yml (default)
+    --singletenant          Use docker-compose.yml
   --list                  List detected backup candidates
   --help                  Show this help
 
@@ -68,12 +71,12 @@ EOF
 
 setup_compose() {
     if docker compose version >/dev/null 2>&1 && docker info >/dev/null 2>&1; then
-        DOCKER_COMPOSE=(docker compose)
+        DOCKER_COMPOSE=(docker compose -f "$SCRIPT_DIR/$COMPOSE_FILE")
         return 0
     fi
 
     if [ -n "$SUDO" ] && $SUDO docker compose version >/dev/null 2>&1 && $SUDO docker info >/dev/null 2>&1; then
-        DOCKER_COMPOSE=($SUDO docker compose)
+        DOCKER_COMPOSE=($SUDO docker compose -f "$SCRIPT_DIR/$COMPOSE_FILE")
         return 0
     fi
 
@@ -459,6 +462,14 @@ parse_args() {
                 RESTART_SERVICES=true
                 shift
                 ;;
+            --multitenant)
+                COMPOSE_FILE="docker-compose-multitenant.yml"
+                shift
+                ;;
+            --singletenant)
+                COMPOSE_FILE="docker-compose.yml"
+                shift
+                ;;
             --list)
                 list_backups
                 exit 0

run-tenant-cmd.sh

@@ -0,0 +1,3 @@
+#!/bin/bash
+# Wrapper to run tenant management fully containerized via docker-compose
+docker compose -f docker-compose-multitenant.yml --profile tools run --rm tenant-manager "$@"

start.sh

@@ -7,6 +7,7 @@ cd "$SCRIPT_DIR"
 ENV_FILE="$SCRIPT_DIR/.docker-build.env"
 APP_IMAGE_REPO="ghcr.io/aiirondev/legendary-octo-garbanzo"
 DIST_DIR="$SCRIPT_DIR/dist"
+RUNTIME_COMPOSE_OVERRIDE_FILE="$SCRIPT_DIR/.docker-compose.runtime.override.yml"
 
 SUDO=""
 if [ "$(id -u)" -ne 0 ] && command -v sudo >/dev/null 2>&1; then
@@ -14,10 +15,13 @@ if [ "$(id -u)" -ne 0 ] && command -v sudo >/dev/null 2>&1; then
 fi
 
 NUITKA_BUILD_VALUE="0"
-HTTP_PORT_VALUE="80"
-HTTPS_PORT_VALUE="443"
+HTTP_PORT_VALUE="8001"
+HTTPS_PORT_VALUE="8443"
 CRON_SETUP_VALUE="${INVENTAR_SETUP_CRON:-1}"
 APP_IMAGE_VALUE="${INVENTAR_APP_IMAGE:-$APP_IMAGE_REPO:latest}"
+COMPOSE_FILE="docker-compose-multitenant.yml"
+COMPOSE_PROFILES_VALUE=""
+MIN_DOCKER_FREE_MB="${INVENTAR_MIN_DOCKER_FREE_MB:-1024}"
 
 usage() {
     cat <<EOF
@@ -26,6 +30,8 @@ Usage: $0 [options]
 Options:
   --no-cron         Do not create or update cron jobs
   --with-cron       Create/update cron jobs (default)
+  --multitenant     Use the multi-tenant architecture deployment
+    --singletenant    Use the legacy single-tenant compose deployment
   -h, --help        Show this help message
 EOF
 }
@@ -41,6 +47,14 @@ parse_args() {
                 CRON_SETUP_VALUE="1"
                 shift
                 ;;
+            --multitenant)
+                COMPOSE_FILE="docker-compose-multitenant.yml"
+                shift
+                ;;
+            --singletenant)
+                COMPOSE_FILE="docker-compose.yml"
+                shift
+                ;;
             -h|--help)
                 usage
                 exit 0
@@ -427,6 +441,16 @@ resolve_app_image() {
     fi
 }
 
+configure_cloudflared_profile() {
+    if [ -f /etc/cloudflared/credentials.json ]; then
+        COMPOSE_PROFILES_VALUE="cloudflare"
+        echo "Cloudflared tunnel: enabled (homeserver)"
+    else
+        COMPOSE_PROFILES_VALUE=""
+        echo "Cloudflared tunnel: disabled (missing /etc/cloudflared/credentials.json)"
+    fi
+}
+
 port_in_use() {
     local port="$1"
 
@@ -450,7 +474,7 @@ stack_owns_host_port() {
     local container_port="$2"
     local mapped_port
 
-    mapped_port="$(docker compose --env-file "$ENV_FILE" port nginx "$container_port" 2>/dev/null | tail -n1 || true)"
+    mapped_port="$(docker compose -f "$COMPOSE_FILE" --env-file "$ENV_FILE" port nginx "$container_port" 2>/dev/null | tail -n1 || true)"
     if [ -z "$mapped_port" ]; then
         return 1
     fi
@@ -493,20 +517,20 @@ configure_host_ports() {
         requested_http="$(awk -F= '/^INVENTAR_HTTP_PORT=/{print $2}' "$ENV_FILE" | tr -d ' ' || true)"
     fi
     if [ -z "$requested_http" ]; then
-        requested_http="80"
+        requested_http="8001"
     fi
 
     if stack_owns_host_port "$requested_http" "80"; then
         HTTP_PORT_VALUE="$requested_http"
     elif port_in_use "$requested_http"; then
-        stop_host_nginx_services || true
+        
 
         if ! port_in_use "$requested_http"; then
             HTTP_PORT_VALUE="$requested_http"
             echo "Freed HTTP port $requested_http by stopping host nginx service"
         else
             HTTP_PORT_VALUE="$(find_free_port 8080)"
-            echo "HTTP port 80 is in use. Using fallback HTTP port: $HTTP_PORT_VALUE"
+            echo "HTTP port is in use. Using fallback HTTP port: $HTTP_PORT_VALUE"
         fi
     else
         HTTP_PORT_VALUE="$requested_http"
@@ -518,13 +542,13 @@ configure_host_ports() {
     fi
 
     if [ -z "$requested_https" ]; then
-        requested_https="443"
+        requested_https="8443"
     fi
 
     if stack_owns_host_port "$requested_https" "443"; then
         HTTPS_PORT_VALUE="$requested_https"
     elif port_in_use "$requested_https"; then
-        stop_host_nginx_services || true
+        
 
         if ! port_in_use "$requested_https"; then
             HTTPS_PORT_VALUE="$requested_https"
@@ -533,12 +557,43 @@ configure_host_ports() {
         fi
 
         HTTPS_PORT_VALUE="$(find_free_port 8443)"
-        echo "HTTPS port 443 is in use. Using fallback HTTPS port: $HTTPS_PORT_VALUE"
+        echo "HTTPS port is in use. Using fallback HTTPS port: $HTTPS_PORT_VALUE"
     else
         HTTPS_PORT_VALUE="$requested_https"
     fi
 }
 
+ensure_min_docker_disk_space() {
+    local docker_root available_kb available_mb
+
+    if ! command -v df >/dev/null 2>&1; then
+        return 0
+    fi
+
+    docker_root="$(docker info --format '{{.DockerRootDir}}' 2>/dev/null || true)"
+    if [ -z "$docker_root" ]; then
+        docker_root="/var/lib/docker"
+    fi
+
+    if [ ! -d "$docker_root" ]; then
+        return 0
+    fi
+
+    available_kb="$(df -Pk "$docker_root" 2>/dev/null | awk 'NR==2 {print $4}' || true)"
+    if [ -z "$available_kb" ]; then
+        return 0
+    fi
+
+    available_mb=$((available_kb / 1024))
+
+    if [ "$available_mb" -lt "$MIN_DOCKER_FREE_MB" ]; then
+        echo "Error: low disk space in Docker data root ($docker_root)."
+        echo "Available: ${available_mb} MB; required minimum: ${MIN_DOCKER_FREE_MB} MB"
+        echo "MongoDB may fail with 'No space left on device'. Free space and retry."
+        exit 1
+    fi
+}
+
 write_env_file() {
     cat > "$ENV_FILE" <<EOF
 NUITKA_BUILD=$NUITKA_BUILD_VALUE
@@ -548,9 +603,24 @@ INVENTAR_APP_IMAGE=$APP_IMAGE_VALUE
 EOF
 }
 
+write_runtime_compose_override() {
+    cat > "$RUNTIME_COMPOSE_OVERRIDE_FILE" <<EOF
+services:
+  app:
+    working_dir: /app/Web
+    command: ["gunicorn", "app:app", "--bind", "0.0.0.0:8000", "--workers", "2", "--timeout", "30", "--graceful-timeout", "20", "--max-requests", "200", "--max-requests-jitter", "50", "--log-level", "info", "--access-logfile", "-", "--error-logfile", "-"]
+    image: ${APP_IMAGE_VALUE}
+    build: null
+EOF
+}
+
 verify_stack_health() {
     local compose_args running_services retry_count=0
-    compose_args=(--env-file "$ENV_FILE")
+    compose_args=(-f "$COMPOSE_FILE")
+    if [ -f "$RUNTIME_COMPOSE_OVERRIDE_FILE" ]; then
+        compose_args+=(-f "$RUNTIME_COMPOSE_OVERRIDE_FILE")
+    fi
+    compose_args+=(--env-file "$ENV_FILE")
 
     # Try health check with optional restart on first failure
     while [[ $retry_count -lt 2 ]]; do
@@ -600,12 +670,27 @@ ensure_runtime_config_json
 setup_scheduled_jobs
 configure_nuitka_mode
 resolve_app_image
+configure_cloudflared_profile
 configure_host_ports
+ensure_min_docker_disk_space
 ensure_app_image_loaded
 write_env_file
+write_runtime_compose_override
 
 echo "Starting Inventarsystem Docker stack (app + mongodb)..."
-docker compose --env-file "$ENV_FILE" up -d --remove-orphans
+compose_up_args=(-f "$COMPOSE_FILE")
+if [ -f "$RUNTIME_COMPOSE_OVERRIDE_FILE" ]; then
+    compose_up_args+=(-f "$RUNTIME_COMPOSE_OVERRIDE_FILE")
+fi
+compose_up_args+=(--env-file "$ENV_FILE")
+if [ -n "$COMPOSE_PROFILES_VALUE" ]; then
+    export COMPOSE_PROFILES="$COMPOSE_PROFILES_VALUE"
+fi
+if ! docker compose "${compose_up_args[@]}" up -d --remove-orphans; then
+    echo "Docker Compose startup failed once. Waiting briefly and retrying..."
+    sleep 5
+    docker compose "${compose_up_args[@]}" up -d --remove-orphans
+fi
 
 verify_stack_health
 

stop.sh

@@ -4,12 +4,30 @@ set -euo pipefail
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 cd "$SCRIPT_DIR"
 
+COMPOSE_FILE="docker-compose-multitenant.yml"
+
+while [[ $# -gt 0 ]]; do
+    case "$1" in
+        --multitenant)
+            COMPOSE_FILE="docker-compose-multitenant.yml"
+            shift
+            ;;
+        --singletenant)
+            COMPOSE_FILE="docker-compose.yml"
+            shift
+            ;;
+        *)
+            shift
+            ;;
+    esac
+done
+
 if ! command -v docker >/dev/null 2>&1; then
     echo "Error: docker command not found. Install Docker first."
     exit 1
 fi
 
 echo "Stopping Inventarsystem Docker stack..."
-docker compose down
+docker compose -f "$COMPOSE_FILE" down
 
 echo "Stack stopped."

update.sh

@@ -15,6 +15,9 @@ APP_IMAGE_ASSET_PREFIX="inventarsystem-image-"
 ENV_FILE="$PROJECT_DIR/.docker-build.env"
 APP_IMAGE_REPO="ghcr.io/aiirondev/legendary-octo-garbanzo"
 DIST_DIR="$PROJECT_DIR/dist"
+COMPOSE_FILE="docker-compose-multitenant.yml"
+MIN_ROOT_FREE_MB="${INVENTAR_MIN_ROOT_FREE_MB:-2048}"
+DIST_KEEP_COUNT="${INVENTAR_DIST_KEEP_COUNT:-2}"
 
 mkdir -p "$LOG_DIR"
 chmod 777 "$LOG_DIR" 2>/dev/null || true
@@ -118,6 +121,65 @@ server {
     return 301 https://$host$request_uri;
 }
 
+ensure_min_root_disk_space() {
+    local available_kb available_mb
+
+    if ! command -v df >/dev/null 2>&1; then
+        return 0
+    fi
+
+    available_kb="$(df -Pk "$PROJECT_DIR" 2>/dev/null | awk 'NR==2 {print $4}' || true)"
+    if [ -z "$available_kb" ]; then
+        return 0
+    fi
+
+    available_mb=$((available_kb / 1024))
+    if [ "$available_mb" -lt "$MIN_ROOT_FREE_MB" ]; then
+        log_message "ERROR: Low disk space on filesystem containing $PROJECT_DIR"
+        log_message "Available: ${available_mb} MB; required minimum: ${MIN_ROOT_FREE_MB} MB"
+        log_message "Free disk space and rerun update."
+        exit 1
+    fi
+}
+
+cleanup_old_dist_artifacts() {
+    local keep_count
+    keep_count="$DIST_KEEP_COUNT"
+
+    if [ ! -d "$DIST_DIR" ]; then
+        return 0
+    fi
+
+    if ! [[ "$keep_count" =~ ^[0-9]+$ ]]; then
+        keep_count=2
+    fi
+
+    mapfile -t archives < <(find "$DIST_DIR" -maxdepth 1 -type f \( -name 'inventarsystem-image-*.tar.gz' -o -name 'inventarsystem-image-*.tar' \) -printf '%T@ %p\n' | sort -nr | awk '{print $2}')
+    if [ "${#archives[@]}" -le "$keep_count" ]; then
+        return 0
+    fi
+
+    local index old_archive deleted=0
+    for (( index=keep_count; index<${#archives[@]}; index++ )); do
+        old_archive="${archives[$index]}"
+        if rm -f "$old_archive"; then
+            deleted=$((deleted + 1))
+        fi
+    done
+
+    if [ "$deleted" -gt 0 ]; then
+        log_message "Cleaned up $deleted old dist image archive(s)"
+    fi
+}
+
+cleanup_docker_dangling_images() {
+    if docker image prune -f >> "$LOG_FILE" 2>&1; then
+        log_message "Cleaned up dangling Docker images"
+    else
+        log_message "WARNING: Could not prune dangling Docker images"
+    fi
+}
+
 server {
     listen 443 ssl;
     server_name _;
@@ -148,6 +210,41 @@ EOF
     fi
 }
 
+usage() {
+    cat <<EOF
+Usage: $0 [options]
+
+Options:
+  --multitenant      Use docker-compose-multitenant.yml (default)
+  --singletenant     Use docker-compose.yml
+  -h, --help         Show this help message
+EOF
+}
+
+parse_args() {
+    while [[ $# -gt 0 ]]; do
+        case "$1" in
+            --multitenant)
+                COMPOSE_FILE="docker-compose-multitenant.yml"
+                shift
+                ;;
+            --singletenant)
+                COMPOSE_FILE="docker-compose.yml"
+                shift
+                ;;
+            -h|--help)
+                usage
+                exit 0
+                ;;
+            *)
+                log_message "ERROR: Unknown option: $1"
+                usage
+                exit 2
+                ;;
+        esac
+    done
+}
+
 archive_logs() {
     log_message "Checking for monthly log archival..."
     if [ -x "$PROJECT_DIR/archive-logs.sh" ]; then
@@ -325,18 +422,48 @@ download_and_extract_bundle() {
         cp -f "$tmp_dir/update.sh" "$PROJECT_DIR/update.sh"
     fi
 
+    # Neu: Multi-Tenant Ressourcen kopieren, falls vorhanden
+    if [ -f "$tmp_dir/docker-compose-multitenant.yml" ]; then
+        cp -f "$tmp_dir/docker-compose-multitenant.yml" "$PROJECT_DIR/docker-compose-multitenant.yml"
+    fi
+    if [ -f "$tmp_dir/docker/nginx/multitenant.conf" ]; then
+        cp -f "$tmp_dir/docker/nginx/multitenant.conf" "$PROJECT_DIR/docker/nginx/multitenant.conf"
+    fi
+    if [ -f "$tmp_dir/manage-tenant.sh" ]; then
+        cp -f "$tmp_dir/manage-tenant.sh" "$PROJECT_DIR/manage-tenant.sh"
+    fi
+    if [ -f "$tmp_dir/run-tenant-cmd.sh" ]; then
+        cp -f "$tmp_dir/run-tenant-cmd.sh" "$PROJECT_DIR/run-tenant-cmd.sh"
+    fi
+    for file in "MULTITENANT_DEPLOYMENT.md" "MULTITENANT_PYTHON_API.md"; do
+        if [ -f "$tmp_dir/$file" ]; then
+            cp -f "$tmp_dir/$file" "$PROJECT_DIR/$file"
+        fi
+    done
+
+    # Ensure executable permissions on all copied scripts
+    chmod +x "$PROJECT_DIR/start.sh" "$PROJECT_DIR/stop.sh" "$PROJECT_DIR/restart.sh" "$PROJECT_DIR/update.sh" "$PROJECT_DIR/backup.sh" "$PROJECT_DIR/init-admin.sh" "$PROJECT_DIR/manage-tenant.sh" "$PROJECT_DIR/run-tenant-cmd.sh" 2>/dev/null || true 2>/dev/null || true
+    chmod +x "$PROJECT_DIR"/manage-tenant.sh "$PROJECT_DIR"/run-tenant-cmd.sh 2>/dev/null || true
+
     if [ ! -f "$PROJECT_DIR/config.json" ] && [ -f "$tmp_dir/config.json" ]; then
         cp -f "$tmp_dir/config.json" "$PROJECT_DIR/config.json"
         log_message "Installed default config.json from release bundle"
     fi
 
-    chmod +x "$PROJECT_DIR/start.sh" "$PROJECT_DIR/stop.sh" "$PROJECT_DIR/restart.sh" "$PROJECT_DIR/update.sh" "$PROJECT_DIR/backup.sh"
+    chmod +x "$PROJECT_DIR/start.sh" "$PROJECT_DIR/stop.sh" "$PROJECT_DIR/restart.sh" "$PROJECT_DIR/update.sh" "$PROJECT_DIR/backup.sh" "$PROJECT_DIR/init-admin.sh" "$PROJECT_DIR/manage-tenant.sh" "$PROJECT_DIR/run-tenant-cmd.sh" 2>/dev/null || true
 }
 
 deploy() {
     local tag="$1"
     local meta_file="$2"
     local app_image="${APP_IMAGE_REPO}:${tag}"
+    local compose_path
+
+    compose_path="$PROJECT_DIR/$COMPOSE_FILE"
+    if [ ! -f "$compose_path" ]; then
+        log_message "ERROR: compose file not found: $compose_path"
+        exit 1
+    fi
 
     cd "$PROJECT_DIR"
     if [ ! -f "$ENV_FILE" ]; then
@@ -362,15 +489,15 @@ EOF
         fi
     fi
 
-    docker compose --env-file "$ENV_FILE" pull nginx mongodb >> "$LOG_FILE" 2>&1
-    docker compose --env-file "$ENV_FILE" up -d --remove-orphans >> "$LOG_FILE" 2>&1
+    docker compose -f "$compose_path" --env-file "$ENV_FILE" pull nginx mongodb >> "$LOG_FILE" 2>&1
+    docker compose -f "$compose_path" --env-file "$ENV_FILE" up -d --remove-orphans >> "$LOG_FILE" 2>&1
     docker tag "$app_image" "$APP_IMAGE_REPO:latest" >> "$LOG_FILE" 2>&1 || true
 }
 
 verify_stack_health() {
     local compose_args running_services
     local https_port
-    compose_args=(--env-file "$ENV_FILE")
+    compose_args=(-f "$PROJECT_DIR/$COMPOSE_FILE" --env-file "$ENV_FILE")
     https_port="$(awk -F= '/^INVENTAR_HTTPS_PORT=/{print $2}' "$ENV_FILE" | tr -d ' ')"
     if [ -z "$https_port" ]; then
         https_port="443"
@@ -395,6 +522,8 @@ verify_stack_health() {
 }
 
 main() {
+    parse_args "$@"
+
     ensure_runtime_dependencies
     ensure_tls_certificates
     ensure_nginx_config_mount_source
@@ -404,6 +533,7 @@ main() {
     require_cmd docker
     require_cmd python3
 
+    ensure_min_root_disk_space
     archive_logs
     create_backup
 
@@ -491,6 +621,8 @@ main() {
     fi
 
     echo "$latest_tag" > "$STATE_FILE"
+    cleanup_old_dist_artifacts
+    cleanup_docker_dangling_images
     log_message "Update completed successfully to release $latest_tag"
 }