refactor: centralize UI design tokens and implement reusable glass-panel and button styles

src/NexusReader.UI.Shared/Pages/Account/Profile.razor.css

@@ -119,23 +119,10 @@
 }
 
 .glass-panel {
-    background: rgba(20, 20, 20, 0.8); /* Fallback */
-    border: 1px solid rgba(255, 255, 255, 0.08);
-    border-radius: 24px;
     padding: 32px;
-    transition: all 0.3s ease;
-}
-
-@supports (backdrop-filter: blur(12px)) {
-    .glass-panel {
-        background: rgba(255, 255, 255, 0.03);
-        backdrop-filter: blur(12px);
-        -webkit-backdrop-filter: blur(12px);
-    }
 }
 
 .glass-panel:hover {
-    background: rgba(255, 255, 255, 0.05);
     border-color: rgba(0, 255, 153, 0.2);
     transform: translateY(-4px);
 }
@@ -289,38 +276,21 @@
     gap: 16px;
 }
 
-.btn-nexus {
+.profile-actions .btn-nexus {
     padding: 12px 24px;
-    border-radius: 12px;
     font-size: 0.9rem;
-    font-weight: 700;
-    cursor: pointer;
-    transition: all 0.2s ease;
-    display: flex;
-    align-items: center;
-    gap: 8px;
-    border: none;
 }
 
-.btn-nexus.secondary {
-    background: rgba(255, 255, 255, 0.05);
-    color: #fff;
-    border: 1px solid rgba(255, 255, 255, 0.1);
-}
-
-.btn-nexus.secondary:hover {
-    background: rgba(255, 255, 255, 0.1);
-}
-
-.btn-nexus.logout {
+.profile-actions .btn-nexus.logout {
     background: rgba(255, 71, 87, 0.1);
     color: #ff4757;
     border: 1px solid rgba(255, 71, 87, 0.2);
 }
 
-.btn-nexus.logout:hover {
+.profile-actions .btn-nexus.logout:hover {
     background: #ff4757;
     color: #fff;
+    box-shadow: 0 4px 15px rgba(255, 71, 87, 0.4);
 }
 
 /* Decorations */