diff --git a/models.py b/models.py
index 597b234..e275d1b 100644
--- a/models.py
+++ b/models.py
@@ -81,6 +81,10 @@ class User(db.Model, UserMixin):
     def is_admin(self):
         return self.role == 'admin'
 
+    @is_admin.setter
+    def is_admin(self, value):
+        self.role = 'admin' if value else 'user'
+
 class Category(db.Model):
     """Wissenschaftliche Kategorien für die Gliederung der öffentlichen Mindmap"""
     id = db.Column(db.Integer, primary_key=True)
diff --git a/static/css/base-styles.css b/static/css/base-styles.css
index 4bb2600..4a8b140 100644
--- a/static/css/base-styles.css
+++ b/static/css/base-styles.css
@@ -457,22 +457,23 @@ body:not(.dark) a:hover {
 /* Light Mode Buttons */
 body:not(.dark) .btn,
 body:not(.dark) button:not(.toggle) {
-    background-color: var(--light-primary);
+    background: linear-gradient(135deg, #6d28d9, #5b21b6);
     color: white;
     border: none;
-    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
+    box-shadow: 0 2px 4px rgba(91, 33, 182, 0.25);
     border-radius: 8px;
     padding: 0.625rem 1.25rem;
     transition: all 0.2s ease;
     font-weight: 600;
     letter-spacing: 0.02em;
+    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
 }
 
 body:not(.dark) .btn:hover,
 body:not(.dark) button:not(.toggle):hover {
-    background-color: var(--light-primary-hover);
+    background: linear-gradient(135deg, #7c3aed, #6d28d9);
     transform: translateY(-1px);
-    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
+    box-shadow: 0 4px 12px rgba(109, 40, 217, 0.3);
 }
 
 /* Dark/Light Mode Switch Button */
@@ -583,36 +584,36 @@ body:not(.dark) .card:hover {
 
 /* Light Mode Buttons mit verbesserter Lesbarkeit */
 body:not(.dark) .btn-primary {
-    background: linear-gradient(135deg, #7c3aed, #6d28d9);
+    background: linear-gradient(135deg, #6d28d9, #5b21b6);
     color: white;
     border: none;
     transition: all 0.2s ease;
-    text-shadow: 0 1px 1px rgba(0, 0, 0, 0.3);
+    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.4);
     font-weight: 600;
     letter-spacing: 0.02em;
-    box-shadow: 0 2px 4px rgba(109, 40, 217, 0.2);
+    box-shadow: 0 2px 4px rgba(91, 33, 182, 0.3);
     border-radius: 8px;
 }
 
 body:not(.dark) .btn-primary:hover {
-    background: linear-gradient(135deg, #8b5cf6, #7c3aed);
-    box-shadow: 0 4px 12px rgba(124, 58, 237, 0.3), 0 2px 4px rgba(0, 0, 0, 0.1);
+    background: linear-gradient(135deg, #7c3aed, #6d28d9);
+    box-shadow: 0 4px 12px rgba(109, 40, 217, 0.4), 0 2px 4px rgba(0, 0, 0, 0.1);
     transform: translateY(-1px);
 }
 
 body:not(.dark) .btn-secondary {
-    background: white;
+    background: linear-gradient(135deg, #ffffff, #f9fafb);
     color: #1f2937;
     border: 2px solid #e5e7eb;
     font-weight: 600;
-    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
+    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.08);
     border-radius: 8px;
 }
 
 body:not(.dark) .btn-secondary:hover {
-    background: #f9fafb;
+    background: linear-gradient(135deg, #f9fafb, #f3f4f6);
     border-color: #d1d5db;
-    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
+    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.12);
     transform: translateY(-1px);
 }
 
diff --git a/utils/user_manager.py b/utils/user_manager.py
index 081fff0..77234f3 100644
--- a/utils/user_manager.py
+++ b/utils/user_manager.py
@@ -55,7 +55,7 @@ def create_user(username, email, password, is_admin=False):
             user = User(
                 username=username,
                 email=email,
-                is_admin=is_admin,
+                role='admin' if is_admin else 'user',
                 created_at=datetime.utcnow()
             )
             user.set_password(password)