diff --git a/App.tsx b/App.tsx
index 28169f5..a967197 100644
--- a/App.tsx
+++ b/App.tsx
@@ -95,14 +95,20 @@ const App: React.FC = () => {
     localStorage.setItem(PERSONA_STORAGE_KEY, JSON.stringify(personas));
   }, [personas]);
 
-  const handleLogin = (email: string) => {
-    // If we have users loaded (from NC or Init), check them
-    const user = users.find(u => u.email.toLowerCase() === email.toLowerCase() && u.status === 'aktiv');
-    if (user) {
-      setCurrentUser(user);
-    } else {
-      alert("Zugang verweigert. Nur verifizierte Wohnpro-Bewohner können sich im Wohnpro Guide anmelden.");
-    }
+  const handleLogin = (email: string): Promise<boolean> => {
+    return new Promise((resolve) => {
+      setTimeout(() => {
+        const user = users.find(u => u.email.toLowerCase() === email.toLowerCase() && u.status === 'aktiv');
+        if (user) {
+          setCurrentUser(user);
+          resolve(true);
+        } else {
+          // In a real app, you'd show a proper error message.
+          // alert("Zugang verweigert. Nur verifizierte Wohnpro-Bewohner können sich im Wohnpro Guide anmelden.");
+          resolve(false);
+        }
+      }, 1500); // Simulate network delay
+    });
   };
 
   const sendMessage = async (text: string) => {
diff --git a/components/Icons.tsx b/components/Icons.tsx
index 6d8f925..addc63b 100644
--- a/components/Icons.tsx
+++ b/components/Icons.tsx
@@ -46,3 +46,20 @@ export const ChevronDownIcon = ({ className = "w-6 h-6" }) => <ChevronDown class
 export const ThumbsUpIcon = ({ className = "w-6 h-6" }) => <ThumbsUp className={className} />;
 export const ThumbsDownIcon = ({ className = "w-6 h-6" }) => <ThumbsDown className={className} />;
 export const DownloadIcon = ({ className = "w-6 h-6" }) => <Download className={className} />;
+
+export const SpinnerIcon = ({ className = "w-6 h-6" }) => (
+    <svg
+      xmlns="http://www.w3.org/2000/svg"
+      width="24"
+      height="24"
+      viewBox="0 0 24 24"
+      fill="none"
+      stroke="currentColor"
+      strokeWidth="2"
+      strokeLinecap="round"
+      strokeLinejoin="round"
+      className={`${className} animate-spin`}
+    >
+      <path d="M21 12a9 9 0 1 1-6.219-8.56" />
+    </svg>
+  );
diff --git a/components/LoginView.tsx b/components/LoginView.tsx
index a7c3c0b..2da5d12 100644
--- a/components/LoginView.tsx
+++ b/components/LoginView.tsx
@@ -1,23 +1,31 @@
 
 import React, { useState } from 'react';
 import { User } from '../types';
+import { SpinnerIcon } from './Icons';
 
 interface LoginViewProps {
-  onLogin: (email: string) => void;
+  onLogin: (email: string) => Promise<boolean>;
   error?: string;
 }
 
 const LoginView: React.FC<LoginViewProps> = ({ onLogin, error: externalError }) => {
   const [email, setEmail] = useState('');
   const [error, setError] = useState(externalError || '');
+  const [isLoading, setIsLoading] = useState(false);
 
-  const handleSubmit = (e: React.FormEvent) => {
+  const handleSubmit = async (e: React.FormEvent) => {
     e.preventDefault();
+    setError('');
     if (!email) {
       setError('Bitte gib deine Wohnpro E-Mail Adresse ein.');
       return;
     }
-    onLogin(email);
+    setIsLoading(true);
+    const success = await onLogin(email);
+    if (!success) {
+      setError('E-Mail Adresse nicht gefunden oder inaktiv.');
+      setIsLoading(false);
+    }
   };
 
   return (
@@ -42,15 +50,17 @@ const LoginView: React.FC<LoginViewProps> = ({ onLogin, error: externalError })
               onChange={(e) => { setEmail(e.target.value); setError(''); }}
               placeholder="Wohnpro E-Mail Adresse"
               className={`w-full bg-gray-50 border ${error ? 'border-red-200' : 'border-gray-100'} rounded-2xl px-6 py-4 focus:outline-none focus:ring-2 focus:ring-black/5 transition-all text-lg placeholder:text-gray-300`}
+              disabled={isLoading}
             />
             {error && <p className="mt-2 text-sm text-red-500 text-left px-2">{error}</p>}
           </div>
 
           <button
             type="submit"
-            className="w-full bg-black text-white rounded-2xl py-4 font-semibold text-lg hover:bg-gray-900 active:scale-[0.98] transition-all shadow-lg shadow-black/5"
+            className="w-full bg-black text-white rounded-2xl py-4 font-semibold text-lg hover:bg-gray-900 active:scale-[0.98] transition-all shadow-lg shadow-black/5 flex items-center justify-center disabled:opacity-50 disabled:cursor-not-allowed"
+            disabled={isLoading}
           >
-            Guide öffnen
+            {isLoading ? <SpinnerIcon /> : 'Guide öffnen'}
           </button>
         </form>