diff --git a/frontend/vite-project/src/components/FileExplorer.css b/frontend/vite-project/src/components/FileExplorer.css
index 649837d..d6b0fe5 100644
--- a/frontend/vite-project/src/components/FileExplorer.css
+++ b/frontend/vite-project/src/components/FileExplorer.css
@@ -1,59 +1,207 @@
 .file-explorer {
   background: var(--explorer-bg, #252526);
   border: 1px solid var(--explorer-border, #404040);
-  border-radius: 4px;
-  margin-bottom: 20px;
+  border-radius: 0.25rem;
+  margin-bottom: 1.25rem;
+  width: 100%;
+  max-width: 20rem;
+  min-width: 3rem;
+  position: relative;
+  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
+  display: flex;
+  flex-direction: column;
+  height: 100%;
+}
+
+.file-explorer.collapsed {
+  max-width: 3.5rem;
+  min-width: 3.5rem;
+}
+
+.file-explorer.mobile-open .file-explorer-content {
+  transform: translateX(0);
+}
+
+/* Mobile and responsive controls */
+.mobile-toggle-btn {
+  display: none;
+  position: fixed;
+  top: 1rem;
+  left: 1rem;
+  z-index: 1001;
+  background: var(--btn-primary-bg, #007acc);
+  border: none;
+  border-radius: 0.375rem;
+  width: 2.5rem;
+  height: 2.5rem;
+  cursor: pointer;
+  transition: all 0.2s ease;
+  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
+}
+
+.mobile-toggle-btn:hover {
+  background: var(--btn-primary-hover, #0086d1);
+  transform: scale(1.05);
+}
+
+.hamburger {
+  width: 1.25rem;
+  height: 1rem;
+  position: relative;
+  display: inline-block;
+}
+
+.hamburger::before,
+.hamburger::after,
+.hamburger {
+  border-top: 2px solid white;
+}
+
+.hamburger::before,
+.hamburger::after {
+  content: '';
+  position: absolute;
+  width: 100%;
+}
+
+.hamburger::before {
+  top: 0.25rem;
+}
+
+.hamburger::after {
+  top: 0.5rem;
+}
+
+.sidebar-toggle-btn {
+  position: absolute;
+  top: 0.5rem;
+  right: -0.75rem;
+  z-index: 10;
+  background: var(--btn-primary-bg, #007acc);
+  border: none;
+  border-radius: 50%;
+  width: 1.5rem;
+  height: 1.5rem;
+  cursor: pointer;
+  transition: all 0.2s ease;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  font-size: 0.75rem;
+  color: white;
+  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
+}
+
+.sidebar-toggle-btn:hover {
+  background: var(--btn-primary-hover, #0086d1);
+  transform: scale(1.1);
+}
+
+.toggle-icon {
+  transition: transform 0.2s ease;
+}
+
+.toggle-icon.collapsed {
+  transform: rotate(180deg);
+}
+
+.file-explorer-content {
+  display: flex;
+  flex-direction: column;
+  height: 100%;
+  width: 100%;
+  transition: transform 0.3s ease;
+}
+
+.mobile-overlay {
+  display: none;
+  position: fixed;
+  top: 0;
+  left: 0;
+  right: 0;
+  bottom: 0;
+  background: rgba(0, 0, 0, 0.5);
+  z-index: 999;
 }
 
 .file-explorer-header {
   display: flex;
   justify-content: space-between;
   align-items: center;
-  padding: 8px 12px;
+  padding: 0.5rem 0.75rem;
   background: var(--explorer-header-bg, #2d2d2d);
   border-bottom: 1px solid var(--explorer-border, #404040);
-  border-radius: 4px 4px 0 0;
+  border-radius: 0.25rem 0.25rem 0 0;
+  flex-shrink: 0;
 }
 
 /* File Actions Toolbar */
 .file-actions-toolbar {
   display: flex;
-  flex-wrap: wrap;
-  gap: 8px;
-  padding: 8px 12px;
+  flex-direction: column;
+  gap: 0.5rem;
+  padding: 0.5rem 0.75rem;
   background: var(--explorer-bg, #252526);
   border-bottom: 1px solid var(--explorer-border, #404040);
+  flex-shrink: 0;
+}
+
+.file-explorer.collapsed .file-actions-toolbar {
+  padding: 0.25rem;
 }
 
 .file-actions-toolbar .import-actions,
 .file-actions-toolbar .export-actions {
   display: flex;
-  flex-wrap:wrap;
-  gap: 8px;
-  width:100%;
+  gap: 0.375rem;
+  align-items: center;
+  flex-wrap: nowrap;
+  width: 100%;
+}
+
+.file-explorer.collapsed .file-actions-toolbar .import-actions,
+.file-explorer.collapsed .file-actions-toolbar .export-actions {
+  flex-direction: column;
+  gap: 0.25rem;
+  width: 100%;
 }
 
 .file-actions-toolbar button {
   flex: 1;
-  min-width: 120px;
+  min-width: 0;
+  max-width: none;
   justify-content: center;
   white-space: nowrap;
   display: flex;
   align-items: center;
-  gap: 6px;
-  padding: 8px 12px;
-  border-radius: 4px;
+  gap: 0.375rem;
+  padding: 0.375rem 0.5rem;
+  border-radius: 0.25rem;
   border: 1px solid var(--btn-border, #555);
   background: var(--btn-bg, #3a3d41);
   color: var(--btn-text, #e0e0e0);
-  font-size: 13px;
+  font-size: 0.75rem;
   cursor: pointer;
   transition: all 0.2s ease;
+  flex-shrink: 1;
+  overflow: hidden;
+  text-overflow: ellipsis;
+}
+
+.file-explorer.collapsed .file-actions-toolbar button {
+  padding: 0.375rem;
+  min-width: 2rem;
+  justify-content: center;
+}
+
+.file-explorer.collapsed .file-actions-toolbar button .btn-text {
+  display: none;
 }
 
 .file-actions-toolbar button:hover {
   background: var(--btn-hover-bg, #4a4e54);
   border-color: var(--btn-hover-border, #666);
+  transform: translateY(-1px);
 }
 
 .file-actions-toolbar .import-files-btn {
@@ -100,9 +248,13 @@
 
 .file-explorer-header h3 {
   margin: 0;
-  font-size: 14px;
+  font-size: 0.875rem;
   font-weight: 600;
   color: var(--explorer-text, #cccccc);
+  transition: all 0.2s ease;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
 }
 
 .file-actions {
@@ -141,42 +293,50 @@
   background: var(--btn-primary-bg, #007acc);
   border: none;
   color: white;
-  width: 24px;
-  height: 24px;
-  border-radius: 3px;
+  width: 1.5rem;
+  height: 1.5rem;
+  border-radius: 0.1875rem;
   cursor: pointer;
-  font-size: 16px;
+  font-size: 1rem;
   font-weight: bold;
   display: flex;
   align-items: center;
   justify-content: center;
-  transition: background-color 0.2s ease;
+  transition: all 0.2s ease;
+  flex-shrink: 0;
 }
 
 .new-file-btn:hover {
   background: var(--btn-primary-hover, #0086d1);
+  transform: scale(1.05);
 }
 
 .new-file-form-container {
-  padding: 12px;
+  padding: 0.75rem;
   background: var(--form-bg, #1e1e1e);
   border-bottom: 1px solid var(--explorer-border, #404040);
+  flex-shrink: 0;
+}
+
+.file-explorer.collapsed .new-file-form-container {
+  padding: 0.5rem;
 }
 
 .new-file-form {
   display: flex;
   flex-direction: column;
-  gap: 8px;
+  gap: 0.5rem;
 }
 
 .new-file-input {
   background: var(--input-bg, #3c3c3c);
   border: 1px solid var(--input-border, #555555);
   color: var(--input-text, #ffffff);
-  padding: 6px 8px;
-  border-radius: 3px;
-  font-size: 13px;
+  padding: 0.375rem 0.5rem;
+  border-radius: 0.1875rem;
+  font-size: 0.8125rem;
   outline: none;
+  transition: border-color 0.2s ease;
 }
 
 .new-file-input:focus {
@@ -185,17 +345,34 @@
 
 .new-file-buttons {
   display: flex;
-  gap: 6px;
+  gap: 0.375rem;
   justify-content: flex-end;
 }
 
+.file-explorer.collapsed .new-file-buttons {
+  justify-content: center;
+}
+
 .create-btn, .cancel-btn {
-  padding: 4px 12px;
+  padding: 0.25rem 0.75rem;
   border: none;
-  border-radius: 3px;
-  font-size: 12px;
+  border-radius: 0.1875rem;
+  font-size: 0.75rem;
   cursor: pointer;
   transition: all 0.2s ease;
+  min-width: 0;
+  flex-shrink: 0;
+}
+
+.file-explorer.collapsed .create-btn,
+.file-explorer.collapsed .cancel-btn {
+  padding: 0.25rem;
+  min-width: 1.5rem;
+  width: 1.5rem;
+  height: 1.5rem;
+  display: flex;
+  align-items: center;
+  justify-content: center;
 }
 
 .create-btn {
@@ -205,6 +382,7 @@
 
 .create-btn:hover {
   background: var(--btn-success-hover, #218838);
+  transform: translateY(-1px);
 }
 
 .cancel-btn {
@@ -214,23 +392,36 @@
 
 .cancel-btn:hover {
   background: var(--btn-secondary-hover, #5a6268);
+  transform: translateY(-1px);
 }
 
 .file-tabs-container {
   display: flex;
   flex-direction: column;
-  gap: 2px;
-  padding: 8px;
-  max-height: 300px;
+  gap: 0.125rem;
+  padding: 0.5rem;
+  max-height: 18.75rem;
   overflow-y: auto;
+  flex-grow: 1;
+  min-height: 0;
+}
+
+.file-explorer.collapsed .file-tabs-container {
+  padding: 0.25rem;
 }
 
 .no-files-message {
-  padding: 20px;
+  padding: 1.25rem;
   text-align: center;
   color: var(--text-muted, #888888);
   font-style: italic;
-  font-size: 13px;
+  font-size: 0.8125rem;
+  line-height: 1.4;
+}
+
+.file-explorer.collapsed .no-files-message {
+  padding: 0.5rem 0.25rem;
+  font-size: 0.75rem;
 }
 
 .context-menu {
@@ -291,7 +482,7 @@
 
 /* Scrollbar styling */
 .file-tabs-container::-webkit-scrollbar {
-  width: 6px;
+  width: 0.375rem;
 }
 
 .file-tabs-container::-webkit-scrollbar-track {
@@ -300,7 +491,7 @@
 
 .file-tabs-container::-webkit-scrollbar-thumb {
   background: var(--scrollbar-thumb, #404040);
-  border-radius: 3px;
+  border-radius: 0.1875rem;
 }
 
 .file-tabs-container::-webkit-scrollbar-thumb:hover {
@@ -317,4 +508,234 @@
 
 .light-mode .file-tabs-container::-webkit-scrollbar-thumb:hover {
   background: var(--scrollbar-thumb-hover, #a8a8a8);
-}
\ No newline at end of file
+}
+
+/* Responsive Media Queries */
+
+/* Tablet and smaller desktop */
+@media (max-width: 1024px) {
+  .file-explorer {
+    max-width: 16rem;
+  }
+  
+  .file-actions-toolbar {
+    gap: 0.25rem;
+    padding: 0.375rem 0.5rem;
+  }
+  
+  .file-actions-toolbar .import-actions,
+  .file-actions-toolbar .export-actions {
+    gap: 0.25rem;
+  }
+  
+  .file-actions-toolbar button {
+    font-size: 0.7rem;
+    padding: 0.25rem 0.375rem;
+    gap: 0.25rem;
+    min-width: 0;
+    flex: 1;
+  }
+  
+  .file-actions-toolbar button .btn-text {
+    font-size: 0.65rem;
+    white-space: nowrap;
+    overflow: hidden;
+    text-overflow: ellipsis;
+  }
+  
+  .sidebar-toggle-btn {
+    display: flex;
+  }
+}
+
+/* Mobile landscape and smaller tablets */
+@media (max-width: 768px) {
+  .sidebar-toggle-btn {
+    display: none !important;
+  }
+  
+  .mobile-toggle-btn {
+    display: flex !important;
+  }
+  
+  .mobile-overlay {
+    display: block !important;
+  }
+  
+  .file-explorer {
+    position: fixed !important;
+    top: 0 !important;
+    left: 0 !important;
+    height: 100vh !important;
+    max-width: 20rem !important;
+    min-width: 20rem !important;
+    width: 20rem !important;
+    z-index: 1000 !important;
+    margin: 0 !important;
+    border-radius: 0 !important;
+    transform: translateX(-100%) !important;
+    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1) !important;
+  }
+  
+  .file-explorer.mobile-open {
+    transform: translateX(0) !important;
+  }
+  
+  .file-explorer.collapsed {
+    max-width: 20rem !important;
+    min-width: 20rem !important;
+    width: 20rem !important;
+  }
+  
+  .file-explorer-content {
+    height: 100vh !important;
+    overflow: hidden !important;
+  }
+  
+  .file-tabs-container {
+    max-height: none !important;
+    flex-grow: 1 !important;
+    padding: 0.75rem !important;
+  }
+  
+  .file-actions-toolbar {
+    flex-direction: column !important;
+    gap: 0.5rem !important;
+    padding: 0.75rem !important;
+  }
+  
+  .file-actions-toolbar .import-actions,
+  .file-actions-toolbar .export-actions {
+    justify-content: stretch !important;
+    flex-direction: row !important;
+    gap: 0.375rem !important;
+  }
+  
+  .file-actions-toolbar button {
+    flex: 1 !important;
+    justify-content: center !important;
+    min-width: 0 !important;
+    max-width: none !important;
+    font-size: 0.75rem !important;
+    padding: 0.5rem 0.375rem !important;
+    white-space: nowrap !important;
+    overflow: hidden !important;
+    text-overflow: ellipsis !important;
+  }
+  
+  .file-actions-toolbar button .btn-text {
+    display: inline !important;
+    font-size: 0.7rem !important;
+  }
+}
+
+/* Mobile portrait */
+@media (max-width: 480px) {
+  .file-explorer {
+    max-width: 16rem !important;
+    min-width: 16rem !important;
+  }
+  
+  .file-explorer.mobile-open {
+    max-width: 16rem !important;
+    min-width: 16rem !important;
+  }
+  
+  .mobile-toggle-btn {
+    width: 2.25rem;
+    height: 2.25rem;
+  }
+  
+  .file-actions-toolbar {
+    padding: 0.5rem !important;
+    gap: 0.375rem !important;
+  }
+  
+  .file-actions-toolbar .import-actions,
+  .file-actions-toolbar .export-actions {
+    gap: 0.25rem !important;
+  }
+  
+  .file-actions-toolbar button {
+    font-size: 0.7rem !important;
+    padding: 0.375rem 0.25rem !important;
+    gap: 0.125rem !important;
+  }
+  
+  .file-actions-toolbar button .btn-text {
+    font-size: 0.65rem !important;
+  }
+  
+  .new-file-form-container {
+    padding: 0.5rem;
+  }
+  
+  .file-tabs-container {
+    padding: 0.5rem;
+  }
+}
+
+/* Very small screens */
+@media (max-width: 360px) {
+  .file-explorer {
+    max-width: 14rem;
+    min-width: 14rem;
+  }
+  
+  .file-explorer.mobile-open {
+    max-width: 14rem;
+    min-width: 14rem;
+  }
+}
+
+/* High DPI screens */
+@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
+  .mobile-toggle-btn,
+  .sidebar-toggle-btn,
+  .new-file-btn {
+    border: 0.5px solid rgba(255, 255, 255, 0.1);
+  }
+}
+
+/* Reduced motion preference */
+@media (prefers-reduced-motion: reduce) {
+  .file-explorer,
+  .file-explorer-content,
+  .mobile-toggle-btn,
+  .sidebar-toggle-btn,
+  .toggle-icon,
+  .file-actions-toolbar button,
+  .create-btn,
+  .cancel-btn {
+    transition: none;
+  }
+}
+
+/* Focus styles for accessibility */
+.mobile-toggle-btn:focus,
+.sidebar-toggle-btn:focus,
+.new-file-btn:focus,
+.file-actions-toolbar button:focus,
+.create-btn:focus,
+.cancel-btn:focus {
+  outline: 2px solid var(--focus-outline, #007acc);
+  outline-offset: 2px;
+}
+
+/* Print styles */
+@media print {
+  .mobile-toggle-btn,
+  .sidebar-toggle-btn,
+  .file-actions-toolbar,
+  .mobile-overlay {
+    display: none !important;
+  }
+  
+  .file-explorer {
+    position: static;
+    transform: none;
+    max-width: none;
+    border: 1px solid #000;
+    page-break-inside: avoid;
+  }
+}
diff --git a/frontend/vite-project/src/components/FileExplorer.jsx b/frontend/vite-project/src/components/FileExplorer.jsx
index 0cc9389..16ffb7f 100644
--- a/frontend/vite-project/src/components/FileExplorer.jsx
+++ b/frontend/vite-project/src/components/FileExplorer.jsx
@@ -15,6 +15,8 @@ const FileExplorer = ({
   const [showNewFileForm, setShowNewFileForm] = useState(false);
   const [newFileName, setNewFileName] = useState('');
   const [showContextMenu, setShowContextMenu] = useState(null);
+  const [isSidebarCollapsed, setIsSidebarCollapsed] = useState(false);
+  const [isMobileMenuOpen, setIsMobileMenuOpen] = useState(false);
   const fileInputRef = React.useRef(null);
   const folderInputRef = React.useRef(null);
 
@@ -50,6 +52,14 @@ const FileExplorer = ({
     setShowContextMenu(null);
   };
 
+  const toggleSidebar = () => {
+    setIsSidebarCollapsed(!isSidebarCollapsed);
+  };
+
+  const toggleMobileMenu = () => {
+    setIsMobileMenuOpen(!isMobileMenuOpen);
+  };
+
   // Close context menu when clicking outside
   React.useEffect(() => {
     const handleClick = () => closeContextMenu();
@@ -57,6 +67,48 @@ const FileExplorer = ({
     return () => document.removeEventListener('click', handleClick);
   }, []);
 
+  // Handle responsive behavior
+  React.useEffect(() => {
+    const handleResize = () => {
+      const width = window.innerWidth;
+      
+      if (width <= 768) {
+        // Mobile: force collapsed state and ensure mobile menu can be used
+        setIsSidebarCollapsed(true);
+      } else if (width <= 1024) {
+        // Tablet: allow collapsed/expanded but close mobile menu
+        setIsMobileMenuOpen(false);
+      } else {
+        // Desktop: expand sidebar and close mobile menu
+        setIsSidebarCollapsed(false);
+        setIsMobileMenuOpen(false);
+      }
+    };
+
+    // Add event listener
+    window.addEventListener('resize', handleResize);
+    
+    // Call immediately to set initial state
+    handleResize();
+
+    // Cleanup
+    return () => window.removeEventListener('resize', handleResize);
+  }, []);
+
+  // Prevent body scroll when mobile menu is open
+  React.useEffect(() => {
+    if (isMobileMenuOpen) {
+      document.body.style.overflow = 'hidden';
+    } else {
+      document.body.style.overflow = '';
+    }
+
+    // Cleanup on unmount
+    return () => {
+      document.body.style.overflow = '';
+    };
+  }, [isMobileMenuOpen]);
+
   // Import: read selected FileList and create files in room
   const importFileList = async (fileList) => {
     if (!fileList || fileList.length === 0) return;
@@ -144,137 +196,169 @@ const FileExplorer = ({
   };
 
   return (
-    <div className="file-explorer">
-      <div className="file-explorer-header">
-        <h3>Files</h3>
-        <button 
-          className="new-file-btn"
-          onClick={() => setShowNewFileForm(!showNewFileForm)}
-          title="Create new file"
-        >
-          +
-        </button>
-      </div>
+    <div className={`file-explorer ${isSidebarCollapsed ? 'collapsed' : ''} ${isMobileMenuOpen ? 'mobile-open' : ''}`}>
+      {/* Mobile hamburger button */}
+      <button 
+        className="mobile-toggle-btn"
+        onClick={toggleMobileMenu}
+        title="Toggle file explorer"
+      >
+        <span className="hamburger"></span>
+      </button>
 
-      {/* File Actions Toolbar */}
-      <div className="file-actions-toolbar">
-        <div className="import-actions">
-          <button className="import-files-btn" onClick={triggerImportFiles} title="Import files">
-            <span className="icon">📄</span> <span>Import Files</span>
-          </button>
-          <button className="import-folder-btn" onClick={triggerImportFolder} title="Import a folder">
-            <span className="icon">📁</span> <span>Import Folder</span>
+      {/* Sidebar toggle button for desktop */}
+      <button 
+        className="sidebar-toggle-btn"
+        onClick={toggleSidebar}
+        title={isSidebarCollapsed ? "Expand sidebar" : "Collapse sidebar"}
+      >
+        <span className={`toggle-icon ${isSidebarCollapsed ? 'collapsed' : ''}`}>
+          {isSidebarCollapsed ? '→' : '←'}
+        </span>
+      </button>
+
+      <div className="file-explorer-content">
+        <div className="file-explorer-header">
+          <h3>{isSidebarCollapsed ? 'F' : 'Files'}</h3>
+          <button 
+            className="new-file-btn"
+            onClick={() => setShowNewFileForm(!showNewFileForm)}
+            title="Create new file"
+          >
+            +
           </button>
         </div>
-        <div className="export-actions">
-          <button className="export-current-btn" onClick={handleExportCurrent} title="Download active file">
-            <span className="icon">⬇️</span> <span>Export Current</span>
-          </button>
-          <button className="export-all-btn" onClick={handleExportAll} title="Download all files as ZIP">
-            <span className="icon">📦</span> <span>Export All</span>
-          </button>
+
+        {/* File Actions Toolbar */}
+        <div className="file-actions-toolbar">
+          <div className="import-actions">
+            <button className="import-files-btn" onClick={triggerImportFiles} title="Import files">
+              <span className="icon">📄</span> 
+              {!isSidebarCollapsed && <span className="btn-text">Import Files</span>}
+            </button>
+            <button className="import-folder-btn" onClick={triggerImportFolder} title="Import a folder">
+              <span className="icon">📁</span> 
+              {!isSidebarCollapsed && <span className="btn-text">Import Folder</span>}
+            </button>
+          </div>
+          <div className="export-actions">
+            <button className="export-current-btn" onClick={handleExportCurrent} title="Download active file">
+              <span className="icon">⬇</span> 
+              {!isSidebarCollapsed && <span className="btn-text">Export Current</span>}
+            </button>
+            <button className="export-all-btn" onClick={handleExportAll} title="Download all files as ZIP">
+              <span className="icon">📦</span> 
+              {!isSidebarCollapsed && <span className="btn-text">Export All</span>}
+            </button>
+          </div>
+          {/* Hidden inputs for file/folder selection */}
+          <input
+            ref={fileInputRef}
+            type="file"
+            multiple
+            style={{ display: 'none' }}
+            onChange={onFilesSelected}
+          />
+          <input
+            ref={folderInputRef}
+            type="file"
+            webkitdirectory=""
+            directory=""
+            style={{ display: 'none' }}
+            onChange={onFolderSelected}
+          />
         </div>
-        {/* Hidden inputs for file/folder selection */}
-        <input
-          ref={fileInputRef}
-          type="file"
-          multiple
-          style={{ display: 'none' }}
-          onChange={onFilesSelected}
-        />
-        <input
-          ref={folderInputRef}
-          type="file"
-          webkitdirectory=""
-          directory=""
-          style={{ display: 'none' }}
-          onChange={onFolderSelected}
-        />
-      </div>
 
-      {showNewFileForm && (
-        <div className="new-file-form-container">
-          <form onSubmit={handleCreateFile} className="new-file-form">
-            <input
-              type="text"
-              value={newFileName}
-              onChange={(e) => setNewFileName(e.target.value)}
-              placeholder="Enter filename (e.g., main.js)"
-              className="new-file-input"
-              autoFocus
-            />
-            <div className="new-file-buttons">
-              <button type="submit" className="create-btn">Create</button>
-              <button 
-                type="button" 
-                className="cancel-btn"
-                onClick={() => {
-                  setShowNewFileForm(false);
-                  setNewFileName('');
-                }}
-              >
-                Cancel
-              </button>
+        {showNewFileForm && (
+          <div className="new-file-form-container">
+            <form onSubmit={handleCreateFile} className="new-file-form">
+              <input
+                type="text"
+                value={newFileName}
+                onChange={(e) => setNewFileName(e.target.value)}
+                placeholder={isSidebarCollapsed ? "filename.js" : "Enter filename (e.g., main.js)"}
+                className="new-file-input"
+                autoFocus
+              />
+              <div className="new-file-buttons">
+                <button type="submit" className="create-btn">
+                  {isSidebarCollapsed ? '✓' : 'Create'}
+                </button>
+                <button 
+                  type="button" 
+                  className="cancel-btn"
+                  onClick={() => {
+                    setShowNewFileForm(false);
+                    setNewFileName('');
+                  }}
+                >
+                  {isSidebarCollapsed ? '✕' : 'Cancel'}
+                </button>
+              </div>
+            </form>
+          </div>
+        )}
+
+        <div className="file-tabs-container">
+          {files.map((file) => (
+            <div
+              key={file.filename}
+              onContextMenu={(e) => handleContextMenu(e, file.filename)}
+            >
+              <FileTab
+                file={file}
+                isActive={file.filename === activeFile}
+                onClick={() => onFileSwitch(file.filename, userName)}
+                onClose={files.length > 1 ? (filename) => handleFileDelete(filename) : null}
+                onRename={onFileRename}
+                isRenamable={true}
+                isCollapsed={isSidebarCollapsed}
+              />
             </div>
-          </form>
+          ))}
         </div>
-      )}
 
-      <div className="file-tabs-container">
-        {files.map((file) => (
+        {files.length === 0 && (
+          <div className="no-files-message">
+            {isSidebarCollapsed ? 'No files' : 'No files in this room. Create a new file to get started.'}
+          </div>
+        )}
+
+        {/* Context Menu */}
+        {showContextMenu && (
           <div
-            key={file.filename}
-            onContextMenu={(e) => handleContextMenu(e, file.filename)}
+            className="context-menu"
+            style={{
+              position: 'fixed',
+              left: showContextMenu.x,
+              top: showContextMenu.y,
+              zIndex: 1000
+            }}
           >
-            <FileTab
-              file={file}
-              isActive={file.filename === activeFile}
-              onClick={() => onFileSwitch(file.filename, userName)}
-              onClose={files.length > 1 ? (filename) => handleFileDelete(filename) : null}
-              onRename={onFileRename}
-              isRenamable={true}
-            />
+            <button
+              className="context-menu-item"
+              onClick={() => handleFileDelete(showContextMenu.filename)}
+              disabled={files.length <= 1}
+            >
+              {isSidebarCollapsed ? 'Delete' : 'Delete File'}
+            </button>
+            <button
+              className="context-menu-item"
+              onClick={() => {
+                // Trigger rename by simulating double click on the tab
+                closeContextMenu();
+              }}
+            >
+              {isSidebarCollapsed ? 'Rename' : 'Rename File'}
+            </button>
           </div>
-        ))}
+        )}
       </div>
 
-      {files.length === 0 && (
-        <div className="no-files-message">
-          No files in this room. Create a new file to get started.
-        </div>
-      )}
-
-      {/* Context Menu */}
-      {showContextMenu && (
-        <div
-          className="context-menu"
-          style={{
-            position: 'fixed',
-            left: showContextMenu.x,
-            top: showContextMenu.y,
-            zIndex: 1000
-          }}
-        >
-          <button
-            className="context-menu-item"
-            onClick={() => handleFileDelete(showContextMenu.filename)}
-            disabled={files.length <= 1}
-          >
-            Delete File
-          </button>
-          <button
-            className="context-menu-item"
-            onClick={() => {
-              // Trigger rename by simulating double click on the tab
-              closeContextMenu();
-            }}
-          >
-            Rename File
-          </button>
-        </div>
-      )}
+      {/* Mobile overlay */}
+      {isMobileMenuOpen && <div className="mobile-overlay" onClick={toggleMobileMenu}></div>}
     </div>
   );
 };
 
-export default FileExplorer;
+export default FileExplorer;
\ No newline at end of file
diff --git a/frontend/vite-project/src/components/FileTab.css b/frontend/vite-project/src/components/FileTab.css
index 5ca90c3..e69de29 100644
--- a/frontend/vite-project/src/components/FileTab.css
+++ b/frontend/vite-project/src/components/FileTab.css
@@ -1,134 +0,0 @@
-.file-tab {
-  display: flex;
-  align-items: center;
-  padding: 8px 12px;
-  background: var(--tab-bg, #2d2d2d);
-  border: 1px solid var(--tab-border, #404040);
-  border-bottom: none;
-  border-radius: 4px 4px 0 0;
-  cursor: pointer;
-  position: relative;
-  min-width: 120px;
-  max-width: 200px;
-  transition: all 0.2s ease;
-  user-select: none;
-  gap: 6px;
-}
-.typing-indicator {
-  font-size: 0.9rem;
-  color: #888;
-  margin-top: 4px;
-  padding-left: 8px;
-  font-style: italic;
-}
-
-.file-tab:hover {
-  background: var(--tab-hover-bg, #3d3d3d);
-}
-
-.file-tab.active {
-  background: var(--tab-active-bg, #1e1e1e);
-  border-color: var(--tab-active-border, #007acc);
-  border-bottom: 1px solid var(--tab-active-bg, #1e1e1e);
-}
-
-.file-icon {
-  font-size: 14px;
-  flex-shrink: 0;
-}
-
-.file-name {
-  flex: 1;
-  font-size: 13px;
-  color: var(--tab-text, #cccccc);
-  white-space: nowrap;
-  overflow: hidden;
-  text-overflow: ellipsis;
-}
-
-.file-tab.active .file-name {
-  color: var(--tab-active-text, #ffffff);
-}
-
-.file-close-btn {
-  background: none;
-  border: none;
-  color: var(--tab-close, #999999);
-  font-size: 16px;
-  font-weight: bold;
-  cursor: pointer;
-  padding: 0;
-  width: 16px;
-  height: 16px;
-  display: flex;
-  align-items: center;
-  justify-content: center;
-  border-radius: 2px;
-  flex-shrink: 0;
-  opacity: 0;
-  transition: all 0.2s ease;
-}
-
-.file-tab:hover .file-close-btn {
-  opacity: 1;
-}
-
-.file-close-btn:hover {
-  background: var(--tab-close-hover-bg, #ff6b6b);
-  color: white;
-}
-
-.file-modified-indicator {
-  color: var(--tab-modified, #ffa500);
-  font-size: 12px;
-  flex-shrink: 0;
-}
-
-.file-rename-form {
-  flex: 1;
-  margin: 0;
-}
-
-.file-rename-input {
-  width: 100%;
-  background: var(--input-bg, #404040);
-  border: 1px solid var(--input-border, #007acc);
-  color: var(--input-text, #ffffff);
-  padding: 2px 4px;
-  font-size: 13px;
-  border-radius: 2px;
-  outline: none;
-}
-
-/* Light mode styles */
-.light-mode .file-tab {
-  --tab-bg: #f3f3f3;
-  --tab-border: #d0d0d0;
-  --tab-hover-bg: #e8e8e8;
-  --tab-active-bg: #ffffff;
-  --tab-active-border: #007acc;
-  --tab-text: #333333;
-  --tab-active-text: #000000;
-  --tab-close: #666666;
-  --tab-close-hover-bg: #ff6b6b;
-  --tab-modified: #ff8c00;
-  --input-bg: #ffffff;
-  --input-border: #007acc;
-  --input-text: #000000;
-}
-
-/* Animation for new tabs */
-.file-tab {
-  animation: slideInTab 0.2s ease-out;
-}
-
-@keyframes slideInTab {
-  from {
-    opacity: 0;
-    transform: translateY(-10px);
-  }
-  to {
-    opacity: 1;
-    transform: translateY(0);
-  }
-}
diff --git a/frontend/vite-project/src/components/FileTab.jsx b/frontend/vite-project/src/components/FileTab.jsx
index 71fdea9..6fdb83c 100644
--- a/frontend/vite-project/src/components/FileTab.jsx
+++ b/frontend/vite-project/src/components/FileTab.jsx
@@ -12,6 +12,7 @@ const FileTab = ({
   onClose,
   onRename,
   isRenamable = true,
+  isCollapsed = false,
   roomId,
   currentUser
 }) => {
@@ -104,40 +105,44 @@ const FileTab = ({
 
   return (
     <div
-      className={`file-tab ${isActive ? 'active' : ''}`}
+      className={`file-tab ${isActive ? 'active' : ''} ${isCollapsed ? 'collapsed' : ''}`}
       onClick={onClick}
       onDoubleClick={handleDoubleClick}
       title={`${file.filename} - ${isActive ? 'Active' : 'Click to open'}`}
     >
       <span className="file-icon">{getFileIcon(file.filename)}</span>
 
-      {isEditing ? (
-        <form onSubmit={handleSubmit} className="file-rename-form">
-          <input
-            type="text"
-            value={newName}
-            onChange={handleInputChange}
-            onKeyDown={handleKeyDown}
-            onBlur={() => {
-              setIsEditing(false);
-              socket.emit('stopTyping', { roomId, user: currentUser });
-            }}
-            className="file-rename-input"
-            autoFocus
-          />
-        </form>
-      ) : (
-        <span className="file-name">{file.filename}</span>
-      )}
-
-      {onClose && (
-        <button
-          className="file-close-btn"
-          onClick={handleCloseClick}
-          title="Close file"
-        >
-          ×
-        </button>
+      {!isCollapsed && (
+        <>
+          {isEditing ? (
+            <form onSubmit={handleSubmit} className="file-rename-form">
+              <input
+                type="text"
+                value={newName}
+                onChange={handleInputChange}
+                onKeyDown={handleKeyDown}
+                onBlur={() => {
+                  setIsEditing(false);
+                  socket.emit('stopTyping', { roomId, user: currentUser });
+                }}
+                className="file-rename-input"
+                autoFocus
+              />
+            </form>
+          ) : (
+            <span className="file-name">{file.filename}</span>
+          )}
+
+          {onClose && (
+            <button
+              className="file-close-btn"
+              onClick={handleCloseClick}
+              title="Close file"
+            >
+              ×
+            </button>
+          )}
+        </>
       )}
 
       {file.lastModified && !isActive && (
@@ -146,7 +151,7 @@ const FileTab = ({
         </span>
       )}
 
-      <TypingIndicator typingUsers={typingUsers} currentUser={currentUser} />
+      {!isCollapsed && <TypingIndicator typingUsers={typingUsers} currentUser={currentUser} />}
     </div>
   );
 };
diff --git a/frontend/vite-project/src/components/ResizableLayout.css b/frontend/vite-project/src/components/ResizableLayout.css
index 2df7b77..843e56c 100644
--- a/frontend/vite-project/src/components/ResizableLayout.css
+++ b/frontend/vite-project/src/components/ResizableLayout.css
@@ -206,35 +206,33 @@
   height: 35px;
 }
 
-/* Responsive adjustments */
+/* Responsive adjustments - Modified to work with FileExplorer mobile overlay */
 @media (max-width: 768px) {
   .resizable-layout {
-    flex-direction: column;
+    /* Keep flex-direction: row to allow FileExplorer mobile overlay to work */
+    flex-direction: row;
   }
   
   .resizable-sidebar {
-    height: auto;
-    max-height: 30vh;
-    width: 100% !important;
-    min-width: unset;
-    max-width: unset;
+    /* Let FileExplorer handle its own mobile positioning */
+    position: relative;
+    z-index: 1;
   }
   
   .resizable-editor {
-    height: auto;
     flex: 1;
+    /* Ensure editor takes full width when sidebar is mobile overlay */
+    width: 100%;
   }
   
   .resizable-chat {
-    height: 40vh;
-    width: 100% !important;
-    min-width: unset;
-    max-width: unset;
-    border-left: none;
-    border-top: 1px solid var(--border-color);
+    height: 100vh;
+    min-width: 250px;
+    max-width: 350px;
   }
   
-  .resize-handle {
+  /* Hide sidebar resizer on mobile, keep chat resizer */
+  .resize-handle.sidebar-resizer {
     display: none;
   }
   
@@ -515,30 +513,26 @@
 
 @media (max-width: 480px) {
   .resizable-layout {
-    flex-direction: column;
+    /* Keep row layout for very small screens too */
+    flex-direction: row;
   }
   
   .resizable-sidebar {
-    width: 100% !important;
-    max-height: 30vh;
-    min-width: auto;
-    max-width: none;
+    /* FileExplorer handles its own mobile positioning */
+    position: relative;
   }
   
   .resizable-editor {
-    width: 100% !important;
-    min-width: auto;
+    flex: 1;
+    width: 100%;
   }
   
   .resizable-chat {
-    width: 100% !important;
-    min-width: auto;
-    max-width: none;
-    border-left: none;
-    border-top: 1px solid var(--border-color);
+    min-width: 200px;
+    max-width: 280px;
   }
   
-  .resizer {
+  .resize-handle.sidebar-resizer {
     display: none;
   }
 }