refactor: Simplify FilterManager layout by conditionally rendering server statistics and search section based on advanced mode, and remove custom hover effects in App.css for cleaner UI

frontend/src/App.css

@@ -22,12 +22,6 @@
   animation: fadeIn 0.3s ease-out;
 }
 
-/* Custom hover effects */
-.btn:hover {
-  transform: translateY(-1px);
-  transition: all 0.2s ease;
-}
-
 /* Custom focus states */
 .btn:focus,
 .form-control:focus,

frontend/src/FilterManager.jsx

@@ -662,6 +662,7 @@ function FilterManager() {
       )}
 
       {/* Панель статистики */}
+      {mode === 'advanced' && (
         <div className="row mb-4">
           <div className="col-md-3">
             <div className="card card-sm">
@@ -736,8 +737,10 @@ function FilterManager() {
             </div>
           </div>
         </div>
+      )}
 
       {/* Секция управления серверами */}
+      {mode === 'advanced' && (
         <div className="row mb-4">
           <div className="col-12">
             <div className="card">
@@ -886,6 +889,7 @@ function FilterManager() {
             </div>
           </div>
         </div>
+      )}
 
       {/* Секция фильтров выбранного сервера */}
       {selectedServer && (