Implement sidebar toggle in cert.html

Added sidebar toggle functionality with accessibility support.

Author: NovaDev404

web/cert.html

@@ -65,5 +65,65 @@ <h2 id="modalName"></h2>
     </div>
 
     <script src="certManager.js"></script>
+    <script>
+      // sidebar-toggle (minimal) — add to certManager.js end
+(function(){
+  const body = document.body;
+  const hamburger = document.querySelector('.hamburger');
+  if(!hamburger) return;
+  // create overlay node if missing
+  let overlay = document.querySelector('.sidebar-overlay');
+  if(!overlay){
+    overlay = document.createElement('div');
+    overlay.className = 'sidebar-overlay';
+    document.body.appendChild(overlay);
+  }
+
+  function openSidebar(){
+    body.classList.add('sidebar-open');
+    hamburger.setAttribute('aria-expanded','true');
+    // focus first item for keyboard users
+    const first = document.querySelector('.sidebar .sidebar-item');
+    if(first) first.focus();
+  }
+  function closeSidebar(){
+    body.classList.remove('sidebar-open');
+    hamburger.setAttribute('aria-expanded','false');
+    hamburger.focus();
+  }
+  function toggleSidebar(){
+    if(body.classList.contains('sidebar-open')) closeSidebar();
+    else openSidebar();
+  }
+
+  hamburger.addEventListener('click', (e) => {
+    e.stopPropagation();
+    toggleSidebar();
+  });
+
+  overlay.addEventListener('click', closeSidebar);
+  document.addEventListener('keydown', (e) => {
+    if(e.key === 'Escape' && body.classList.contains('sidebar-open')) closeSidebar();
+  });
+
+  // auto-close on menu item click for small screens
+  document.addEventListener('click', (e) => {
+    const item = e.target.closest('.sidebar-item');
+    if(!item) return;
+    if(window.innerWidth <= 860){
+      setTimeout(closeSidebar, 160);
+    }
+  });
+
+  // keep state sane when resizing/rotating
+  window.addEventListener('resize', () => {
+    if(window.innerWidth > 860) {
+      body.classList.remove('sidebar-open');
+      hamburger.setAttribute('aria-expanded','false');
+    }
+  });
+})();
+
+    </script>
   </body>
 </html>