🔧 Fix remaining white page-stat-card elements

- Updated .page-stat-card background to dark theme
- Changed border-left color to cyan accent
- Updated h3 text color to white
- Fixed close button hover color
- All page statistics cards now fully dark

public/css/admin-dashboard.css

@@ -224,7 +224,7 @@ body {
 }
 
 .close:hover {
-    color: #000;
+    color: #ffffff;
 }
 
 .form-group {
@@ -371,14 +371,15 @@ body {
 }
 
 .page-stat-card {
-    background: #f8f9fa;
+    background: rgba(26, 26, 46, 0.95);
     border-radius: 8px;
     padding: 20px;
-    border-left: 4px solid #1e3c72;
+    border-left: 4px solid #00d4ff;
+    border: 1px solid rgba(255, 255, 255, 0.1);
 }
 
 .page-stat-card h3 {
-    color: #1e3c72;
+    color: #ffffff;
     margin-bottom: 15px;
     font-size: 1.2em;
 }