diff --git a/Website/main.py b/Website/main.py
index dbb66c2..5c73a61 100644
--- a/Website/main.py
+++ b/Website/main.py
@@ -1972,34 +1972,54 @@ def preise():
 @app.route('/preise/book-option', methods=['POST'])
 @login_required
 def book_option_package():
-    package_raw = _sanitize_text(request.form.get("package") or "", 40).lower()
+    # Unterstützt "packages" (Warenkorb) und Fallback auf "package" (altes Formular)
+    packages_raw = _sanitize_text(request.form.get("packages") or request.form.get("package") or "", 200).lower()
     booking_flow = _sanitize_text(request.form.get("flow") or "payment", 24).lower()
+    
     if booking_flow not in BOOKING_FLOW_MAP:
         booking_flow = "payment"
 
-    selected_package = BOOKING_PACKAGE_MAP.get(package_raw)
-    if not selected_package:
-        flash("Ungültige Buchungsoption ausgewählt.", "error")
+    if not packages_raw:
+        flash("Keine Buchungsoption ausgewählt.", "error")
         return redirect(url_for("preise"))
 
-    return redirect(url_for("booking_payment", package=package_raw, flow=booking_flow))
+    return redirect(url_for("booking_payment", packages=packages_raw, flow=booking_flow))
 
 
 @app.route('/booking/payment', methods=['GET', 'POST'])
 @login_required
 def booking_payment():
-    package_raw = _sanitize_text((request.values.get("package") or ""), 40).lower()
-    booking_flow = _sanitize_text((request.values.get("flow") or "payment"), 24).lower()
+    # Hole kommagetrennte Liste (z. B. "inventarsystem,terminverwaltung")
+    packages_str = _sanitize_text(request.values.get("packages") or request.values.get("package") or "", 200).lower()
+    booking_flow = _sanitize_text(request.values.get("flow") or "payment", 24).lower()
+    
     if booking_flow not in BOOKING_FLOW_MAP:
         booking_flow = "payment"
 
-    selected_package = BOOKING_PACKAGE_MAP.get(package_raw)
-    package_price = BOOKING_PRICE_MAP.get(package_raw)
-    if not selected_package:
-        flash("Ungültige Buchungsoption ausgewählt.", "error")
+    if not packages_str:
+        flash("Keine Buchungsoption ausgewählt.", "error")
         return redirect(url_for("preise"))
 
+    package_list = [p.strip() for p in packages_str.split(',') if p.strip()]
+    
+    # Validiere Pakete, sammle Namen und berechne Gesamtpreis
+    selected_package_names = []
+    total_price = 0.0
+    for pkg in package_list:
+        name = BOOKING_PACKAGE_MAP.get(pkg)
+        if name:
+            selected_package_names.append(name)
+            total_price += BOOKING_PRICE_MAP.get(pkg, 0.0)
+        else:
+            flash(f"Ungültige Buchungsoption: {pkg}", "error")
+            return redirect(url_for("preise"))
+            
+    # Zusammengefasster String für Frontend und Datenbank (z.B. "Inventarsystem, Terminplaner")
+    selected_package = ", ".join(selected_package_names)
+    package_raw = packages_str # Speichert alle raw-keys für DB
+
     flow_config = BOOKING_FLOW_MAP[booking_flow]
+    
     form_data = {
         "contact_person": _sanitize_text(request.values.get("contact_person") or "", 120),
         "school_name": _sanitize_text(request.values.get("school_name") or "", 160),
@@ -2018,7 +2038,7 @@ def booking_payment():
     review_data = {
         "package": selected_package,
         "package_key": package_raw,
-        "package_price": package_price,
+        "package_price": total_price,
         "flow": booking_flow,
         "title": flow_config["title"],
         "intro": flow_config["intro"],
@@ -2031,6 +2051,7 @@ def booking_payment():
     if request.method == "GET":
         return render_template("schnell_buchung.html", **review_data)
 
+    # --- POST Logik & Validierung ---
     required_fields = {
         "contact_person": "Ansprechpartner",
         "school_name": "Schule/Einrichtung",
@@ -2039,6 +2060,7 @@ def booking_payment():
         "billing_zip": "PLZ",
         "billing_city": "Ort",
     }
+    
     missing_labels = [label for key, label in required_fields.items() if not form_data.get(key)]
     if missing_labels:
         flash(f"Bitte folgende Pflichtfelder ausfüllen: {', '.join(missing_labels)}.", "error")
@@ -2079,20 +2101,17 @@ def booking_payment():
                     "message": message,
                     "created_at": _utc_now_iso(),
                     "booking_flow": booking_flow,
-                    "booking_package": package_raw,
+                    "booking_package": package_raw, # Hier steht nun z.B. "inventarsystem,terminverwaltung"
                     "booking_data": form_data,
                 }
             )
+            
         if booking_flow == "payment":
-            # Do NOT create an invoice directly. Instead request provisioning via server_steering
             booking_number = f"BOOK-{datetime.utcnow().strftime('%Y%m%d%H%M%S')}"
 
-            # Build a subdomain from the school name (fallback to username)
-            # Use lowercase, sanitized school name and check for existing instances.
             raw_base = form_data.get("school_name") or session.get("username") or booking_number
             base = _slugify_subdomain(raw_base).lower()[:51]
 
-            # Check existing instances and require the user to choose a different name on conflict
             try:
                 existing = steering.instace.list() or []
             except Exception:
@@ -2103,11 +2122,10 @@ def booking_payment():
                 return render_template("schnell_buchung.html", **review_data)
 
             subdomain = base[:63]
-
             provision_status = "not_started"
             provision_port = None
             provision_error = ""
-            provision_config_ok = False
+            provision_config_ok = True # Startet mit True, wird False wenn ein Modul fehlschlägt
 
             try:
                 try:
@@ -2115,6 +2133,7 @@ def booking_payment():
                 except Exception as e:
                     port = False
                     provision_error = str(e)
+                    provision_config_ok = False
 
                 if port and port is not False:
                     provision_status = "started"
@@ -2123,19 +2142,24 @@ def booking_payment():
                     except Exception:
                         provision_port = port
 
-                    # Configure module if applicable
-                    module = None
-                    if package_raw in {"inventarsystem", "buecherei", "terminverwaltung", "emailversand", "starter", "advanced"}:
-                        module = package_raw
-                    if module:
+                    # Multi-Modul-Konfiguration: Startpaket wird in Inventar + Bücherei aufgeschlüsselt
+                    modules_to_provision = set()
+                    for pkg in package_list:
+                        if pkg == "startpaket":
+                            modules_to_provision.update(["inventarsystem", "buecherei"])
+                        elif pkg in {"inventarsystem", "buecherei", "terminverwaltung", "emailversand", "starter", "advanced"}:
+                            modules_to_provision.add(pkg)
+                    
+                    # Einzelne Module in der erstellten Instanz editieren/aktivieren
+                    for mod in modules_to_provision:
                         try:
-                            edit_ok = steering.instace.edit(subdomain, module)
-                            provision_config_ok = bool(edit_ok)
-                            if not provision_config_ok and not provision_error:
-                                provision_error = f"Module configuration failed for {module}"
+                            edit_ok = steering.instace.edit(subdomain, mod)
+                            if not edit_ok:
+                                provision_config_ok = False
+                                provision_error += f" | Edit failed for {mod}"
                         except Exception as e:
                             provision_config_ok = False
-                            provision_error = str(e)
+                            provision_error += f" | {mod}: {str(e)}"
                 else:
                     provision_status = "failed"
                     if not provision_error:
@@ -2149,7 +2173,7 @@ def booking_payment():
                 "booking_number": booking_number,
                 "package": package_raw,
                 "package_label": selected_package,
-                "amount_eur": BOOKING_PRICE_MAP.get(package_raw, 0.0),
+                "amount_eur": total_price,
                 "booking_flow": booking_flow,
                 "booking_data": form_data,
                 "assigned_admin_username": assigned_admin_username,
@@ -2159,7 +2183,7 @@ def booking_payment():
                 "provision_status": provision_status,
                 "provision_port": provision_port or "",
                 "provision_config_ok": provision_config_ok,
-                "provision_error": provision_error,
+                "provision_error": provision_error.strip(" | "),
                 "created_at": _utc_now_iso(),
                 "source": "booking_payment",
             }
@@ -2173,8 +2197,8 @@ def booking_payment():
                     req_client.close()
 
     except PyMongoError:
-        flash("Buchungsanfrage konnte nicht gesendet werden.", "error")
-        return redirect(url_for("booking_payment", package=package_raw, flow=booking_flow))
+        flash("Buchungsanfrage konnte nicht gesendet werden. Bitte versuchen Sie es erneut.", "error")
+        return redirect(url_for("booking_payment", packages=package_raw, flow=booking_flow))
     finally:
         if client:
             client.close()
@@ -2185,13 +2209,13 @@ def booking_payment():
         else f"Buchung für {selected_package} wurde erfolgreich erfasst. Die Rechnung wird per E-Mail versendet." 
     )
     flash(success_text, "success")
+    
     if booking_flow == "payment":
         return redirect(url_for("my_invoices")) 
     else:
         return redirect(url_for("user_chat"))
 
 
-
 @app.route('/instance_request/delete', methods=['POST'])
 @login_required
 def instance_request_delete():
diff --git a/Website/templates/preise.html b/Website/templates/preise.html
index 05a3990..84db49c 100644
--- a/Website/templates/preise.html
+++ b/Website/templates/preise.html
@@ -5,6 +5,7 @@
 {% block head %}
 {{ super() }}
 <style>
+    /* Hero & Grid Styles (Beibehalten) */
     .booking-hero {
         background: linear-gradient(135deg, rgba(28, 90, 99, 0.14), rgba(255, 255, 255, 0.65)),
                     linear-gradient(180deg, #fffefb 0%, #f2f5f2 100%);
@@ -16,7 +17,6 @@
         overflow: hidden;
         position: relative;
     }
-
     .booking-hero::before {
         content: "";
         position: absolute;
@@ -24,24 +24,9 @@
         background: radial-gradient(circle at top right, rgba(34, 98, 128, 0.16), transparent 36%);
         pointer-events: none;
     }
-
-    .booking-hero > * {
-        position: relative;
-        z-index: 1;
-    }
-
-    .booking-hero h1 {
-        margin-bottom: 0.65rem;
-        color: #133d4a;
-        font-size: clamp(2rem, 3.5vw, 3.2rem);
-    }
-
-    .booking-hero p {
-        margin: 0.75rem 0 0;
-        max-width: 780px;
-        color: #3b5f69;
-        font-size: clamp(1rem, 1.05vw, 1.1rem);
-    }
+    .booking-hero > * { position: relative; z-index: 1; }
+    .booking-hero h1 { margin-bottom: 0.65rem; color: #133d4a; font-size: clamp(2rem, 3.5vw, 3.2rem); }
+    .booking-hero p { margin: 0.75rem 0 0; max-width: 780px; color: #3b5f69; font-size: clamp(1rem, 1.05vw, 1.1rem); }
 
     .packages-grid {
         display: grid;
@@ -63,304 +48,105 @@
         gap: 1.2rem;
         transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
     }
-
-    .package-card:hover {
-        transform: translateY(-3px);
-        border-color: #b2d4dc;
-        box-shadow: 0 24px 48px rgba(23, 44, 57, 0.1);
-    }
-
-    .package-card__header {
-        display: flex;
-        flex-direction: column;
-        justify-content: flex-start;
-        align-items: flex-start;
-        gap: 1.2rem;
-    }
-
-    .package-card__header > div {
-        min-width: 0;
-        width: 100%;
-    }
-
-    .package-card__tag {
-        display: inline-flex;
-        align-items: center;
-        gap: 0.35rem;
-        padding: 0.45rem 0.8rem;
-        border-radius: 999px;
-        background: #e6f5f8;
-        color: #106476;
-        font-size: 0.9rem;
-        font-weight: 700;
-        letter-spacing: 0.01em;
-        margin-bottom: 0.6rem;
-    }
-
-    .package-card__name {
-        margin: 0;
-        color: #143f46;
-        font-size: clamp(1.4rem, 2.5vw, 1.8rem);
-        line-height: 1.2;
-        word-wrap: break-word;
-    }
-
-    .package-card__price {
-        display: inline-flex;
-        align-items: baseline;
-        gap: 0.35rem;
-        font-weight: 700;
-        color: #102d37;
-        white-space: normal;
-        margin-top: 0.2rem;
-    }
-
-    .package-card__price span {
-        font-size: clamp(1.8rem, 3vw, 2.4rem);
-        letter-spacing: -0.04em;
-        line-height: 1.1;
-    }
-    .package-card__old-price {
-        color: #c62828;
-        text-decoration: line-through;
-        margin-right: 0.5rem;
-        font-size: clamp(1rem, 2.2vw, 1.1rem);
-        font-weight: 700;
-        opacity: 0.95;
-    }
-
-    .package-card__new-price {
-        color: #0b6440;
-        font-size: clamp(1.8rem, 3vw, 2.4rem);
-        font-weight: 800;
-        letter-spacing: -0.04em;
-    }
-
-    .package-card__price small {
-        color: #57717b;
-        font-size: 0.95rem;
-    }
-
-    .package-card__description {
-        margin: 0;
-        color: #4b6a72;
-        line-height: 1.75;
-    }
-
-    .package-card__features {
-        margin: 1rem 0 0;
-        padding: 0;
-        list-style: none;
-        display: grid;
-        gap: 0.75rem;
-        flex: 1 1 auto;
-    }
-
-    .package-card__features li {
-        display: grid;
-        grid-template-columns: auto 1fr;
-        gap: 0.75rem;
-        align-items: flex-start;
-        color: #4f6a72;
-        font-size: 0.98rem;
-    }
-
-    .package-card__features li::before {
-        content: "✓";
-        color: #187490;
-        font-weight: 700;
-        line-height: 1.2;
-    }
-
-    .package-card__actions {
-        margin-top: auto;
-        padding-top: 0.25rem;
-    }
-
-    .package-card__actions form,
-    .package-card__actions a {
-        width: 100%;
-        display: inline-flex;
-    }
-
+    .package-card:hover { transform: translateY(-3px); border-color: #b2d4dc; box-shadow: 0 24px 48px rgba(23, 44, 57, 0.1); }
+    .package-card.highlight { border-color: #106476; box-shadow: 0 18px 40px rgba(16, 100, 118, 0.15); }
+    
+    .package-card__header { display: flex; flex-direction: column; gap: 1.2rem; }
+    .package-card__tag { display: inline-flex; align-items: center; gap: 0.35rem; padding: 0.45rem 0.8rem; border-radius: 999px; background: #e6f5f8; color: #106476; font-size: 0.9rem; font-weight: 700; margin-bottom: 0.6rem; }
+    .package-card__tag.highlight-tag { background: #106476; color: white; }
+    .package-card__name { margin: 0; color: #143f46; font-size: clamp(1.4rem, 2.5vw, 1.8rem); line-height: 1.2; }
+    
+    .package-card__price { display: inline-flex; align-items: baseline; gap: 0.35rem; font-weight: 700; color: #102d37; margin-top: 0.2rem; }
+    .package-card__price span { font-size: clamp(1.8rem, 3vw, 2.4rem); letter-spacing: -0.04em; }
+    .package-card__price small { color: #57717b; font-size: 0.95rem; }
+    
+    .package-card__description { margin: 0; color: #4b6a72; line-height: 1.75; }
+    .package-card__features { margin: 1rem 0 0; padding: 0; list-style: none; display: grid; gap: 0.75rem; flex: 1 1 auto; }
+    .package-card__features li { display: grid; grid-template-columns: auto 1fr; gap: 0.75rem; color: #4f6a72; font-size: 0.98rem; }
+    .package-card__features li::before { content: "✓"; color: #187490; font-weight: 700; }
+    
+    .package-card__actions { margin-top: auto; padding-top: 0.25rem; }
+    
     .btn {
-        width: 100%;
-        border: 1px solid #1c5a63;
-        background: linear-gradient(120deg, #1d6d79 0%, #164b55 100%);
-        color: #ffffff;
-        border-radius: 999px;
-        padding: 0.95rem 1.2rem;
-        font-weight: 700;
-        cursor: pointer;
-        text-align: center;
-        transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
+        width: 100%; border: 1px solid #1c5a63; background: linear-gradient(120deg, #1d6d79 0%, #164b55 100%);
+        color: #ffffff; border-radius: 999px; padding: 0.95rem 1.2rem; font-weight: 700;
+        cursor: pointer; text-align: center; transition: all 0.2s ease;
+        display: inline-flex; align-items: center; justify-content: center; gap: 0.5rem;
     }
+    .btn:hover, .btn:focus-visible { transform: translateY(-1px); box-shadow: 0 12px 24px rgba(28, 90, 99, 0.22); }
+    .btn.secondary { border-color: #c7dde3; background: #f7fbfb; color: #1d5f6f; }
+    .btn.outline { background: transparent; color: #1d6d79; }
+    .btn.outline:hover { background: #f0f7f8; }
 
-    .btn:hover,
-    .btn:focus-visible {
-        transform: translateY(-1px);
-        box-shadow: 0 12px 24px rgba(28, 90, 99, 0.22);
-    }
+    .notice { padding: 1.3rem 1.35rem; border-radius: 20px; background: #ffffff; border: 1px solid #dfe7ea; color: #304f5a; box-shadow: 0 12px 24px rgba(23, 44, 57, 0.04); }
+    .notice strong { color: #15444c; }
 
-    .btn.secondary {
-        border-color: #c7dde3;
-        background: #f7fbfb;
-        color: #1d5f6f;
-    }
-
-    .notice {
-        padding: 1.3rem 1.35rem;
-        border-radius: 20px;
-        background: #ffffff;
-        border: 1px solid #dfe7ea;
-        color: #304f5a;
-        box-shadow: 0 12px 24px rgba(23, 44, 57, 0.04);
-    }
-
-    .notice strong {
-        color: #15444c;
-    }
-
-    @media (max-width: 760px) {
-        .booking-hero {
-            padding: 1.5rem 1.2rem;
-            border-radius: 18px;
-        }
-
-        .booking-hero h1 {
-            font-size: 1.8rem;
-        }
-
-        .packages-grid {
-            grid-template-columns: 1fr;
-            gap: 1.2rem;
-        }
-
-        .package-card {
-            padding: 1.4rem 1.2rem;
-            border-radius: 18px;
-            gap: 1rem;
-        }
-
-        .package-card__header {
-            gap: 0.8rem;
-        }
-
-        .package-card__price {
-            margin-top: 0;
-        }
-
-        .package-card__price span {
-            font-size: 2rem;
-        }
-
-        .btn {
-            padding: 1rem 1.2rem;
-            font-size: 1.05rem;
-        }
-    }
-
-    /* Custom Modal Styles */
+    /* Modals */
     .custom-modal {
-        position: fixed;
-        top: 0;
-        left: 0;
-        width: 100%;
-        height: 100%;
-        display: none;
-        align-items: center;
-        justify-content: center;
-        z-index: 100;
-        padding: 1rem;
+        position: fixed; top: 0; left: 0; width: 100%; height: 100%;
+        display: none; align-items: center; justify-content: center; z-index: 1000; padding: 1rem;
     }
-
-    .custom-modal.active {
-        display: flex;
-    }
-
-    .custom-modal-backdrop {
-        position: absolute;
-        top: 0;
-        left: 0;
-        width: 100%;
-        height: 100%;
-        background: rgba(18, 49, 54, 0.4);
-        backdrop-filter: blur(4px);
-    }
-
+    .custom-modal.active { display: flex; }
+    .custom-modal-backdrop { position: absolute; top: 0; left: 0; width: 100%; height: 100%; background: rgba(18, 49, 54, 0.4); backdrop-filter: blur(4px); }
     .custom-modal-content {
-        position: relative;
-        background: #ffffff;
-        border-radius: 20px;
-        padding: 2.2rem;
-        max-width: 500px;
-        width: 100%;
-        box-shadow: 0 24px 54px rgba(23, 44, 57, 0.2);
-        z-index: 101;
+        position: relative; background: #ffffff; border-radius: 20px; padding: 2.2rem;
+        max-width: 550px; width: 100%; box-shadow: 0 24px 54px rgba(23, 44, 57, 0.2); z-index: 101;
         animation: modalEnter 0.3s cubic-bezier(0.16, 1, 0.3, 1);
     }
+    @keyframes modalEnter { from { opacity: 0; transform: translateY(20px) scale(0.95); } to { opacity: 1; transform: translateY(0) scale(1); } }
+    
+    .custom-modal-content h3 { margin-top: 0; margin-bottom: 1rem; color: #133d4a; }
+    .custom-modal-actions { display: flex; gap: 1rem; margin-top: 2rem; justify-content: flex-end; }
+    
+    /* Cart Specific Styles */
+    .cart-items-list { margin: 1.5rem 0; display: flex; flex-direction: column; gap: 1rem; }
+    .cart-item { display: flex; justify-content: space-between; align-items: center; padding: 1rem; background: #f7fbfb; border: 1px solid #e1eced; border-radius: 12px; }
+    .cart-item-info { display: flex; flex-direction: column; }
+    .cart-item-title { font-weight: 700; color: #133d4a; }
+    .cart-item-price { color: #187490; font-size: 0.95rem; }
+    .cart-item-remove { background: none; border: none; color: #c62828; cursor: pointer; font-size: 0.9rem; font-weight: 700; padding: 0.5rem; transition: opacity 0.2s; }
+    .cart-item-remove:hover { opacity: 0.7; }
+    .cart-total-row { display: flex; justify-content: space-between; font-size: 1.2rem; font-weight: 800; color: #133d4a; margin-top: 1rem; padding-top: 1rem; border-top: 2px solid #e1eced; }
 
-    @keyframes modalEnter {
-        from {
-            opacity: 0;
-            transform: translateY(20px) scale(0.95);
-        }
-        to {
-            opacity: 1;
-            transform: translateY(0) scale(1);
-        }
+    /* Floating Cart Button */
+    .floating-cart {
+        position: fixed; bottom: 2rem; right: 2rem; background: #164b55; color: white;
+        width: 65px; height: 65px; border-radius: 50%; display: flex; align-items: center; justify-content: center;
+        box-shadow: 0 10px 25px rgba(22, 75, 85, 0.4); cursor: pointer; z-index: 900;
+        transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
+        display: none; /* Hidden when empty */
     }
-
-    .custom-modal-content h3 {
-        margin-top: 0;
-        margin-bottom: 1rem;
-        color: #133d4a;
+    .floating-cart.visible { display: flex; animation: popIn 0.4s; }
+    .floating-cart:hover { transform: scale(1.08); }
+    .cart-badge {
+        position: absolute; top: -5px; right: -5px; background: #c62828; color: white;
+        font-size: 0.8rem; font-weight: 700; width: 24px; height: 24px; border-radius: 50%;
+        display: flex; align-items: center; justify-content: center; border: 2px solid white;
     }
+    .floating-cart svg { width: 28px; height: 28px; fill: currentColor; }
+    @keyframes popIn { from { transform: scale(0); } to { transform: scale(1); } }
 
-    .custom-modal-content p {
-        color: #4b6a72;
-        margin-bottom: 0.8rem;
-    }
-
-    .custom-modal-actions {
-        display: flex;
-        gap: 1rem;
-        margin-top: 2rem;
-        justify-content: flex-end;
-    }
-
-    .custom-modal-actions button {
-        width: auto;
-        min-width: 120px;
-    }
-
-    @media (max-width: 600px) {
-        .custom-modal-content {
-            padding: 1.6rem;
-            border-radius: 16px;
-        }
-
-        .custom-modal-actions {
-            flex-direction: column;
-        }
-
-        .custom-modal-actions button {
-            width: 100%;
-        }
+    /* Upsell Highlights */
+    .upsell-box { background: #e6f5f8; border: 1px solid #b2d4dc; border-radius: 12px; padding: 1.2rem; margin: 1rem 0; }
+    .upsell-box h4 { margin: 0 0 0.5rem 0; color: #106476; }
+    
+    @media (max-width: 760px) {
+        .custom-modal-actions { flex-direction: column; }
+        .custom-modal-actions button { width: 100%; }
+        .floating-cart { bottom: 1.5rem; right: 1.5rem; width: 55px; height: 55px; }
     }
 </style>
 {% endblock %}
 
 {% block content %}
 <section class="booking-hero">
-    <h1>Preise</h1>
-    <p>Preise zu unseren Modulen
-    <p>Unsere Module und Pakete sind klar strukturiert und transparent. Wählen Sie die passende Lösung für Ihre Schule und senden Sie die Anfrage direkt an unser Admin-Team.</p>
-    <p>Nach der Anfrage wird sich ein Administrator zeitnah über das Portal mit Ihnen in Verbindung setzen, um die Buchung persönlich vor Ort zu besprechen oder einen direkten Start zu vereinbaren.</p>
-    <p>Unsere Server stehen in einem Deutschen Data-Center der Firma Strato und garantieren eine hohe Verfügbarkeit und Sicherheit Ihrer Daten.</p>
+    <h1>Preise & Module</h1>
+    <p>Unsere Module und Pakete sind klar strukturiert und transparent. Stellen Sie sich Ihre Lösung flexibel zusammen.</p>
+    <p>Nach Ihrer Anfrage meldet sich unser Admin-Team, um die Bereitstellung oder einen Termin zur Abstimmung einzuplanen. Die Server stehen in einem deutschen Rechenzentrum (Strato) – DSGVO-konform und hochverfügbar.</p>
 </section>
 
 <section class="packages-grid" aria-label="Buchungspakete">
+    <!-- INVENTARSYSTEM -->
     <article class="package-card">
         <div class="package-card__header">
             <div>
@@ -368,30 +154,28 @@
                 <h2 class="package-card__name">Inventarsystem</h2>
             </div>
             <div class="package-card__price">
-                <span>350 €</span>
-                <small>/ Jahr</small>
+                <span>350 €</span><small>/ Jahr</small>
             </div>
         </div>
-        <p class="package-card__description">Der stabile Einstieg in die Schulverwaltung mit Inventarverwaltung, Benutzerrechten und Berichten für den gesamten Schulbetrieb.</p>
+        <p class="package-card__description">Der stabile Einstieg in die Schulverwaltung mit Inventarverwaltung, Benutzerrechten und Berichten.</p>
         <ul class="package-card__features">
             <li>Inventarverwaltung mit Rollenrechten</li>
             <li>Basis-Support und Ticketing</li>
             <li>Schulweite Übersichten und Berichte</li>
-            <li>Erweiterte Instanzverwaltung</li>
             <li>Ihre Schullehrmittel auf einen Blick</li>
         </ul>
         <div class="package-card__actions">
             {% if 'username' in session %}
-                <form method="POST" action="{{ url_for('book_option_package') }}" class="booking-form">
-                    <input type="hidden" name="package" value="inventarsystem">
-                    <button class="btn" type="button" onclick="openBookingModal(this.form)">Jetzt buchen</button>
-                </form>
+                <button class="btn add-to-cart-btn" data-id="inventarsystem" data-name="Inventarsystem" data-price="350" onclick="handleAddToCart(this)">
+                    In den Warenkorb
+                </button>
             {% else %}
-                <a class="btn secondary" href="{{ url_for('login') }}">Hinweis: Registrieren Sie sich oder loggen sich bitte ein, um einen gemeinsamen Termin zu vereinbaren.</a>
+                <a class="btn secondary" href="{{ url_for('login') }}">Zum Buchen einloggen</a>
             {% endif %}
         </div>
     </article>
 
+    <!-- BIBLIOTHEKSSYSTEM -->
     <article class="package-card">
         <div class="package-card__header">
             <div>
@@ -399,29 +183,27 @@
                 <h2 class="package-card__name">Bibliothekssystem</h2>
             </div>
             <div class="package-card__price">
-                <span>100 €</span>
-                <small>/ Jahr</small>
+                <span>100 €</span><small>/ Jahr</small>
             </div>
         </div>
-        <p class="package-card__description">Ein spezialisiertes Modul für Bibliotheken und Medienzentren mit Ausleihprozessen, Medienbeständen und historischer Transparenz.</p>
+        <p class="package-card__description">Spezialisiertes Modul für Bibliotheken und Medienzentren inkl. Ausleihprozessen und Historie.</p>
         <ul class="package-card__features">
             <li>Ausgabe- und Rückgabeprozesse</li>
             <li>Bestandsübersichten für Medien</li>
             <li>Transparente Historie pro Medium</li>
-            <li></li>
         </ul>
         <div class="package-card__actions">
             {% if 'username' in session %}
-                <form method="POST" action="{{ url_for('book_option_package') }}" class="booking-form">
-                    <input type="hidden" name="package" value="buecherei">
-                    <button class="btn" type="button" onclick="openBookingModal(this.form)">Jetzt buchen</button>
-                </form>
+                <button class="btn add-to-cart-btn" data-id="buecherei" data-name="Bibliothekssystem" data-price="100" onclick="handleAddToCart(this)">
+                    In den Warenkorb
+                </button>
             {% else %}
-                <a class="btn secondary" href="{{ url_for('login') }}">Mit Konto buchen</a>
+                <a class="btn secondary" href="{{ url_for('login') }}">Zum Buchen einloggen</a>
             {% endif %}
         </div>
     </article>
 
+    <!-- TERMINPLANER -->
     <article class="package-card">
         <div class="package-card__header">
             <div>
@@ -429,59 +211,57 @@
                 <h2 class="package-card__name">Terminplaner</h2>
             </div>
             <div class="package-card__price">
-                <span>100 €</span>
-                <small>/ Jahr</small>
+                <span>100 €</span><small>/ Jahr</small>
             </div>
         </div>
-        <p class="package-card__description">Ein für flexible Terminplanung entwickeltes Modul, dass dem Nutzer erlaubt, seine Termine für beispielsweise Elternsprechstunden komfortabel und schnell im Zugriff zu haben.</p>
+        <p class="package-card__description">Für flexible Terminplanung entwickelt (z.B. Elternsprechstunden), um Termine hürdenlos online anzubieten.</p>
         <ul class="package-card__features">
-            <li>Flexible Slot- und Zeitfenster-Erstellung </li>
+            <li>Flexible Slot- und Zeitfenster-Erstellung</li>
             <li>Hürdenlose Buchung ohne Registrierung</li>
-            <li>Echtzeit-Aktualisierung gebuchter Termine</li>
-            <li>Direkte Terminvergabe per Einladungslink</li>
+            <li>Echtzeit-Aktualisierung</li>
+            <li>Terminvergabe per Einladungslink</li>
         </ul>
         <div class="package-card__actions">
             {% if 'username' in session %}
-                <form method="POST" action="{{ url_for('book_option_package') }}" class="booking-form">
-                    <input type="hidden" name="package" value="Terminverwaltung">
-                    <button class="btn" type="button" onclick="openBookingModal(this.form)">Jetzt buchen</button>
-                </form>
+                <button class="btn add-to-cart-btn" data-id="terminverwaltung" data-name="Terminplaner" data-price="100" onclick="handleAddToCart(this)">
+                    In den Warenkorb
+                </button>
             {% else %}
-                <a class="btn secondary" href="{{ url_for('login') }}">Mit Konto buchen</a>
+                <a class="btn secondary" href="{{ url_for('login') }}">Zum Buchen einloggen</a>
             {% endif %}
         </div>
     </article>
 
-    <article class="package-card">
+    <!-- STARTPAKET (Kombi) -->
+    <article class="package-card highlight">
         <div class="package-card__header">
             <div>
-                <span class="package-card__tag">Paket</span>
+                <span class="package-card__tag highlight-tag">Sparpaket</span>
                 <h2 class="package-card__name">Startpaket</h2>
             </div>
             <div class="package-card__price">
-                <span>420 €</span>
-                <small>/ Jahr</small>
+                <span>420 €</span><small>/ Jahr</small>
             </div>
         </div>
-        <p class="package-card__description">Das Starterpaket enhält die Inventarverwaltung und das Bibliothekssystem, als ideale Komplettlösung.</p>
+        <p class="package-card__description">Enthält <strong>Inventarverwaltung</strong> und <strong>Bibliothekssystem</strong> als ideale Komplettlösung zum Vorzugspreis.</p>
         <ul class="package-card__features">
-            <li>Das Inventarsystem idealer start Punkt</li>
-            <li>Das Bibliothekssystem als passende Ergänzung</li>
-            <li>Ein einfaches und intuitive Benutzeroberfläche</li>
-            <li>Der Perfekte Start für Ihre Digitalisierung</li>
+            <li>Beinhaltet alle Features des Inventarsystems</li>
+            <li>Beinhaltet alle Features des Bibliothekssystems</li>
+            <li>Perfekter Start für Ihre Digitalisierung</li>
+            <li><strong>30 € Ersparnis</strong> gegenüber Einzelkauf</li>
         </ul>
         <div class="package-card__actions">
             {% if 'username' in session %}
-                <form method="POST" action="{{ url_for('book_option_package') }}" class="booking-form">
-                    <input type="hidden" name="package" value="Terminverwaltung">
-                    <button class="btn" type="button" onclick="openBookingModal(this.form)">Jetzt buchen</button>
-                </form>
+                <button class="btn add-to-cart-btn" data-id="startpaket" data-name="Startpaket (Inventar + Bibliothek)" data-price="420" onclick="handleAddToCart(this)">
+                    In den Warenkorb
+                </button>
             {% else %}
-                <a class="btn secondary" href="{{ url_for('login') }}">Mit Konto buchen</a>
+                <a class="btn secondary" href="{{ url_for('login') }}">Zum Buchen einloggen</a>
             {% endif %}
         </div>
     </article>
 
+    <!-- SCHULTRÄGER -->
     <article class="package-card">
         <div class="package-card__header">
             <div>
@@ -489,88 +269,238 @@
                 <h2 class="package-card__name">Schulträger</h2>
             </div>
             <div class="package-card__price">
-                <span>Auf Anfrage</span>
+                <span>Individuell</span>
             </div>
         </div>
-        <p class="package-card__description">Individuelles Angebot für Schulträger mit mehreren Schulen und speziellen Anforderungen an die Verwaltung.</p>
+        <p class="package-card__description">Individuelles Angebot für Schulträger mit mehreren Schulen und speziellen Anforderungen.</p>
         <ul class="package-card__features">
             <li>Mandantenfähige Verwaltung</li>
             <li>Zentrale Übersicht aller Schulen</li>
-            <li>Individuelle Anpassungen</li>
+            <li>Individuelle Anpassungen & SSO</li>
             <li>Persönlicher Ansprechpartner</li>
         </ul>
         <div class="package-card__actions">
             {% if 'username' in session %}
-                <form method="POST" action="{{ url_for('book_option_package') }}" class="booking-form">
-                    <input type="hidden" name="package" value="schultraeger">
-                    <button class="btn" type="button" onclick="openBookingModal(this.form)">Jetzt anfragen</button>
-                </form>
+                <button class="btn add-to-cart-btn" data-id="schultraeger" data-name="Schulträger (Individuell)" data-price="0" onclick="handleAddToCart(this)">
+                    Auf die Liste setzen
+                </button>
             {% else %}
-                <a class="btn secondary" href="{{ url_for('login') }}">Mit Konto anfragen</a>
+                <a class="btn secondary" href="{{ url_for('login') }}">Zum Anfragen einloggen</a>
             {% endif %}
         </div>
     </article>
-
 </section>
 
-<section class="notice">
-    {% if 'username' in session %}
-        <p><strong>Hinweis:</strong> Deine Buchungsanfrage wird direkt vom Admin-Team bearbeitet und deiner Schulinstanz zugeordnet.</p>
-    {% else %}
-        <p><strong>Hinweis:</strong> Bitte logge dich ein oder registriere dich, um einen Termin zu vereinbaren.</p>
-    {% endif %}
-</section>
+<!-- Floating Cart Button -->
+<div class="floating-cart" id="cartFab" onclick="openCartModal()">
+    <svg viewBox="0 0 24 24">
+        <path d="M7 18c-1.1 0-1.99.9-1.99 2S5.9 22 7 22s2-.9 2-2-.9-2-2-2zM1 2v2h2l3.6 7.59-1.35 2.45c-.16.28-.25.61-.25.96 0 1.1.9 2 2 2h12v-2H7.42c-.14 0-.25-.11-.25-.25l.03-.12.9-1.63h7.45c.75 0 1.41-.41 1.75-1.03l3.58-6.49c.08-.14.12-.31.12-.48 0-.55-.45-1-1-1H5.21l-.94-2H1zm16 16c-1.1 0-1.99.9-1.99 2s.89 2 1.99 2 2-.9 2-2-.9-2-2-2z"/>
+    </svg>
+    <div class="cart-badge" id="cartBadge">0</div>
+</div>
 
-<!-- Custom Modal -->
-<div class="custom-modal" id="bookingModal" aria-hidden="true" role="dialog" aria-modal="true">
-    <div class="custom-modal-backdrop" onclick="closeBookingModal()"></div>
+<!-- Upsell Modal -->
+<div class="custom-modal" id="upsellModal" aria-hidden="true" role="dialog">
+    <div class="custom-modal-backdrop" onclick="closeUpsellModal()"></div>
     <div class="custom-modal-content">
-        <h3>Buchung bestätigen</h3>
-        <p>Möchten Sie dieses Paket jetzt direkt buchen oder zuerst einen Gesprächstermin vereinbaren?</p>
-        <p style="font-size: 0.95rem;">Bitte wählen sie eine der Beiden Optionen aus um mit dem Verfahren weiter fortzufahren.</p>
+        <h3>Tipp: Sparen Sie mit dem Startpaket!</h3>
+        <p>Sie sind dabei, ein Einzelmodul in den Warenkorb zu legen. Wussten Sie, dass Inventar- und Bibliothekssystem perfekt zusammenarbeiten?</p>
+        
+        <div class="upsell-box">
+            <h4>Das Startpaket (420 € / Jahr)</h4>
+            <p style="font-size: 0.9rem; margin-bottom: 0;">Beinhaltet das Inventarsystem (regulär 350 €) und das Bibliothekssystem (regulär 100 €). Sie sparen 30 € jährlich!</p>
+        </div>
+
         <div class="custom-modal-actions">
-            <button class="btn secondary" type="button" onclick="closeBookingModal()">Abbrechen</button>
-            <button class="btn" type="button" onclick="goToBookingReview('consultation')">Gesprächstermin vereinbaren</button>
-            <button class="btn" type="button" onclick="goToBookingReview('payment')">Buchen</button>
+            <button class="btn outline" type="button" onclick="declineUpsell()">Nein, beim Einzelmodul bleiben</button>
+            <button class="btn" type="button" onclick="acceptUpsell()">Zum Startpaket upgraden</button>
+        </div>
+    </div>
+</div>
+
+<!-- Cart Modal -->
+<div class="custom-modal" id="cartModal" aria-hidden="true" role="dialog">
+    <div class="custom-modal-backdrop" onclick="closeCartModal()"></div>
+    <div class="custom-modal-content">
+        <h3>Ihr Warenkorb</h3>
+        <div id="cartEmptyMessage" style="display:none; color: #4b6a72;">Ihr Warenkorb ist noch leer.</div>
+        
+        <div class="cart-items-list" id="cartItemsContainer">
+            <!-- Items werden per JS hier eingefügt -->
+        </div>
+
+        <div class="cart-total-row" id="cartTotalRow">
+            <span>Gesamtsumme:</span>
+            <span id="cartTotalPrice">0 €</span>
+        </div>
+
+        <div class="custom-modal-actions" id="cartActions">
+            <button class="btn secondary" type="button" onclick="closeCartModal()">Weiter umsehen</button>
+            <button class="btn outline" type="button" onclick="goToCheckout('consultation')">Beratungstermin anfragen</button>
+            <button class="btn" type="button" onclick="goToCheckout('payment')">Jetzt Zahlungspflichtig buchen</button>
         </div>
     </div>
 </div>
 
 <script>
+    // System Config
     const bookingReviewBaseUrl = "{{ url_for('booking_payment') }}";
-    let currentBookingForm = null;
+    
+    // Cart State
+    let cart = []; // Speichert {id, name, price}
+    let pendingItemForUpsell = null;
 
-    function openBookingModal(formElement) {
-        currentBookingForm = formElement;
-        const modal = document.getElementById('bookingModal');
-        modal.classList.add('active');
-        modal.setAttribute('aria-hidden', 'false');
+    // Hilfsfunktion: Warenkorb UI aktualisieren
+    function updateCartUI() {
+        const fab = document.getElementById('cartFab');
+        const badge = document.getElementById('cartBadge');
+        const container = document.getElementById('cartItemsContainer');
+        const emptyMsg = document.getElementById('cartEmptyMessage');
+        const totalRow = document.getElementById('cartTotalRow');
+        const actions = document.getElementById('cartActions');
+        const totalPriceEl = document.getElementById('cartTotalPrice');
+
+        // Badge & FAB Sichtbarkeit
+        if (cart.length > 0) {
+            fab.classList.add('visible');
+            badge.innerText = cart.length;
+            emptyMsg.style.display = 'none';
+            totalRow.style.display = 'flex';
+            actions.style.display = 'flex';
+        } else {
+            fab.classList.remove('visible');
+            emptyMsg.style.display = 'block';
+            totalRow.style.display = 'none';
+            actions.style.display = 'none';
+        }
+
+        // Artikel rendern
+        container.innerHTML = '';
+        let total = 0;
+        let hasIndividualPrice = false;
+
+        cart.forEach(item => {
+            if(item.price > 0) total += item.price;
+            if(item.price === 0) hasIndividualPrice = true;
+
+            const priceText = item.price > 0 ? `${item.price} €` : "Auf Anfrage";
+
+            container.innerHTML += `
+                <div class="cart-item">
+                    <div class="cart-item-info">
+                        <span class="cart-item-title">${item.name}</span>
+                        <span class="cart-item-price">${priceText}</span>
+                    </div>
+                    <button class="cart-item-remove" onclick="removeFromCart('${item.id}')" aria-label="Entfernen">Entfernen</button>
+                </div>
+            `;
+        });
+
+        // Summe formatieren
+        if(hasIndividualPrice && total > 0) {
+            totalPriceEl.innerText = `${total} € + ind. Paket`;
+        } else if (hasIndividualPrice && total === 0) {
+            totalPriceEl.innerText = "Auf Anfrage";
+        } else {
+            totalPriceEl.innerText = `${total} € / Jahr`;
+        }
     }
 
-    function closeBookingModal() {
-        currentBookingForm = null;
-        const modal = document.getElementById('bookingModal');
-        modal.classList.remove('active');
-        modal.setAttribute('aria-hidden', 'true');
-    }
-
-    function goToBookingReview(flow) {
-        if (!currentBookingForm) {
+    // Artikel zum Warenkorb hinzufügen
+    function addItem(id, name, price) {
+        // Prüfen, ob schon drin
+        if(cart.find(i => i.id === id)) {
+            alert(`${name} ist bereits im Warenkorb.`);
             return;
         }
 
-        const packageInput = currentBookingForm.querySelector('input[name="package"]');
-        const packageValue = packageInput ? packageInput.value : '';
+        // Konflikte mit Startpaket abfangen
+        const hasStartpaket = cart.find(i => i.id === 'startpaket');
+        if (hasStartpaket && (id === 'inventarsystem' || id === 'buecherei')) {
+            alert(`Das Modul ist bereits in Ihrem gewählten Startpaket enthalten!`);
+            return;
+        }
+        if (id === 'startpaket') {
+            // Wenn Startpaket hinzugefügt wird, Einzelmodule (Inventar/Bib) entfernen, um doppelte Kosten zu vermeiden
+            cart = cart.filter(i => i.id !== 'inventarsystem' && i.id !== 'buecherei');
+        }
+
+        cart.push({id, name, price: parseInt(price, 10)});
+        updateCartUI();
+        
+        // Modal öffnen zur Bestätigung
+        openCartModal();
+    }
+
+    // Logic Klick auf "In den Warenkorb"
+    function handleAddToCart(btn) {
+        const id = btn.dataset.id;
+        const name = btn.dataset.name;
+        const price = btn.dataset.price;
+
+        // Upsell Logik triggern, wenn Inventar oder Bib einzeln gewählt wird
+        if ((id === 'inventarsystem' || id === 'buecherei') && !cart.find(i => i.id === 'startpaket')) {
+            pendingItemForUpsell = { id, name, price };
+            openUpsellModal();
+        } else {
+            // Normal hinzufügen
+            addItem(id, name, price);
+        }
+    }
+
+    // Artikel aus Warenkorb entfernen
+    function removeFromCart(id) {
+        cart = cart.filter(i => i.id !== id);
+        updateCartUI();
+        if(cart.length === 0) {
+            setTimeout(closeCartModal, 1500); // Modal nach kurzer Zeit schließen wenn leer
+        }
+    }
+
+    // Upsell-Entscheidungen
+    function acceptUpsell() {
+        closeUpsellModal();
+        addItem('startpaket', 'Startpaket (Inventar + Bibliothek)', 420);
+        pendingItemForUpsell = null;
+    }
+
+    function declineUpsell() {
+        closeUpsellModal();
+        if(pendingItemForUpsell) {
+            addItem(pendingItemForUpsell.id, pendingItemForUpsell.name, pendingItemForUpsell.price);
+        }
+        pendingItemForUpsell = null;
+    }
+
+    // Checkout Routing
+    function goToCheckout(flow) {
+        if (cart.length === 0) return;
+        
+        // Alle IDs der Cart zusammenführen (z.B. "startpaket,terminverwaltung")
+        const packageIds = cart.map(i => i.id).join(',');
+        
         const reviewUrl = new URL(bookingReviewBaseUrl, window.location.origin);
-        reviewUrl.searchParams.set('package', packageValue);
+        reviewUrl.searchParams.set('packages', packageIds);
         reviewUrl.searchParams.set('flow', flow);
+        
         window.location.href = reviewUrl.toString();
     }
 
+    // Modal Steuerungen
+    function openCartModal() {
+        updateCartUI();
+        document.getElementById('cartModal').classList.add('active');
+    }
+    function closeCartModal() { document.getElementById('cartModal').classList.remove('active'); }
+    function openUpsellModal() { document.getElementById('upsellModal').classList.add('active'); }
+    function closeUpsellModal() { document.getElementById('upsellModal').classList.remove('active'); }
+
+    // Escape Key für Modals
     document.addEventListener('keydown', function(event) {
         if (event.key === 'Escape') {
-            closeBookingModal();
+            closeCartModal();
+            closeUpsellModal();
         }
     });
 </script>
-{% endblock %}
+{% endblock %}
\ No newline at end of file
diff --git a/Website/templates/schnell_buchung.html b/Website/templates/schnell_buchung.html
index 05f12d9..a86413d 100644
--- a/Website/templates/schnell_buchung.html
+++ b/Website/templates/schnell_buchung.html
@@ -416,6 +416,7 @@
     const form = document.getElementById('checkout-form');
     const errorAlert = document.getElementById('form-error-alert');
     const statusText = document.getElementById('loading-status-text');
+    const spinner = document.querySelector('.spinner'); // Referenz auf den Ladekreis
     
     // Subdomain Live-Prüfung
     const slugInput = document.getElementById('tenant_slug');
@@ -423,17 +424,23 @@
     const submitBtn = document.getElementById('booking_submit');
     let slugTimer = null;
 
+    // OPTIMIERT: Alles im 'input'-Event (fängt auch Maus-Paste und Autocomplete)
     slugInput.addEventListener('input', (e) => {
+        // 1. Sanitization
         e.target.value = e.target.value.toLowerCase().replace(/[^a-z0-9-]/g, '');
-    });
-
-    slugInput.addEventListener('keyup', (e) => {
+        
+        // 2. Debounced API Check
         clearTimeout(slugTimer);
         slugTimer = setTimeout(() => checkSubdomain(e.target.value), 600);
     });
 
     async function checkSubdomain(name) {
-        if (name.length < 3) return;
+        if (name.length < 3) {
+            feedback.textContent = 'Bitte mindestens 3 Zeichen eingeben.';
+            feedback.style.color = '#5e757d';
+            submitBtn.disabled = true;
+            return;
+        }
         try {
             const res = await fetch(`/instance_request/check_subdomain?slug=${name}`);
             const j = await res.json();
@@ -448,6 +455,8 @@
             }
         } catch (e) {
             console.error(e);
+            feedback.textContent = 'Prüfung fehlgeschlagen. Bitte erneut versuchen.';
+            feedback.style.color = '#b02a37';
         }
     }
 
@@ -457,7 +466,11 @@
     form.addEventListener('submit', async (e) => {
         e.preventDefault(); 
         errorAlert.style.display = 'none';
+        
+        // OPTIMIERT: Visuelles Feedback für den initialen Submit
+        const originalBtnText = submitBtn.textContent;
         submitBtn.disabled = true;
+        submitBtn.textContent = "Wird verarbeitet...";
 
         const formData = new FormData(form);
         const tenantSlug = formData.get('tenant_slug');
@@ -486,6 +499,7 @@
             errorAlert.textContent = error.message;
             errorAlert.style.display = 'block';
             submitBtn.disabled = false;
+            submitBtn.textContent = originalBtnText; // Button zurücksetzen
         }
     });
 
@@ -509,9 +523,22 @@
             }
         }, 3500);
 
+        let retryCount = 0;
+        const maxRetries = 30; // OPTIMIERT: Max 90 Sekunden Polling (30 * 3s)
+
         const checkStatus = async () => {
+            retryCount++;
+            
+            // Timeout-Abbruch
+            if (retryCount > maxRetries) {
+                handlePollingError("Zeitüberschreitung. Die Bereitstellung dauert ungewöhnlich lange. Sie werden per E-Mail informiert, sobald das System bereit ist.", msgInterval);
+                return;
+            }
+
             try {
                 const res = await fetch(`/instance_request/status?slug=${slug}`);
+                if (!res.ok) throw new Error("Network response was not ok");
+                
                 const data = await res.json();
 
                 if (data.status === 'ready') {
@@ -520,14 +547,13 @@
                     showSuccessState(data.url, data.username, data.password, data.invoice_url);
                 } else if (data.status === 'failed') {
                     // SETUP FEHLGESCHLAGEN
-                    clearInterval(msgInterval);
-                    statusText.textContent = "Fehler bei der Bereitstellung. Bitte Support kontaktieren.";
-                    statusText.style.color = '#b02a37';
+                    handlePollingError("Fehler bei der Bereitstellung. Bitte kontaktieren Sie unseren Support.", msgInterval);
                 } else {
                     // SETUP LÄUFT NOCH -> in 3 Sekunden erneut prüfen
                     setTimeout(checkStatus, 3000);
                 }
             } catch (err) {
+                // Bei Netzwerkfehler weiter versuchen, solange maxRetries nicht erreicht ist
                 setTimeout(checkStatus, 3000);
             }
         };
@@ -535,6 +561,17 @@
         // Starte den ersten Check nach 2 Sekunden
         setTimeout(checkStatus, 2000);
     }
+    
+    // OPTIMIERT: Hilfsfunktion für Polling-Fehler (verhindert Sackgassen-UI)
+    function handlePollingError(message, intervalId) {
+        clearInterval(intervalId);
+        statusText.textContent = message;
+        statusText.style.color = '#b02a37';
+        if (spinner) spinner.style.display = 'none'; // Spinner ausblenden
+        
+        // Optional: Einen Zurück/Support-Button einfügen
+        statusText.insertAdjacentHTML('afterend', '<br><a href="#" onclick="window.location.reload(); return false;" class="btn secondary" style="margin-top:1rem;">Seite neu laden</a>');
+    }
 
     // ==========================================
     // Erfolgs-Bildschirm anzeigen