*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

    /* :root {
      --bg-base:       #f4f5f9;
      --bg-sidebar:    #ffffff;
      --bg-chat:       #f4f5f9;
      --bg-input:      #ffffff;
      --bg-user-msg:   #e8edff;
      --bg-ai-msg:     #ffffff;
      --border:        rgba(0,0,0,0.08);
      --accent:        #5b7fff;
      --accent-soft:   rgba(91,127,255,0.15);
      --accent-glow:   rgba(91,127,255,0.35);
      --text-primary:  #181a26;
      --text-secondary:#5a5f7a;
      --text-muted:    #a0a4b8;
      --tag-bg:        rgba(91,127,255,0.1);
      --scrollbar:     #d0d3e0;
      --send-bg:       #5b7fff;
      --send-hover:    #7a99ff;
      --shadow:        0 8px 40px rgba(0,0,0,0.08);
      --radius:        14px;
      --transition:    0.22s cubic-bezier(0.4,0,0.2,1);
    }

    [data-theme="light"] {
      --bg-base:       #f4f5f9;
      --bg-sidebar:    #ffffff;
      --bg-chat:       #f4f5f9;
      --bg-input:      #ffffff;
      --bg-user-msg:   #e8edff;
      --bg-ai-msg:     #ffffff;
      --border:        rgba(0,0,0,0.08);
      --text-primary:  #181a26;
      --text-secondary:#5a5f7a;
      --text-muted:    #a0a4b8;
      --tag-bg:        rgba(91,127,255,0.1);
      --scrollbar:     #d0d3e0;
      --shadow:        0 8px 40px rgba(0,0,0,0.08);
    }

    html, body { height: 100%; font-family: Poppins, Helvetica, "sans-serif"; background: var(--bg-base); color: var(--text-primary); transition: background var(--transition), color var(--transition); } */

    :root {
      --bg-base:       #0d0e12;
      --bg-sidebar:    #111318;
      --bg-chat:       #0d0e12;
      --bg-input:      #1a1c24;
      --bg-user-msg:   #1e2235;
      --bg-ai-msg:     #141720;
      --border:        rgba(255,255,255,0.07);
      --accent:        #5b7fff;
      --accent-soft:   rgba(91,127,255,0.15);
      --accent-glow:   rgba(91,127,255,0.35);
      --text-primary:  #eef0f7;
      --text-secondary:#8b8fa8;
      --text-muted:    #555a72;
      --tag-bg:        rgba(91,127,255,0.12);
      --scrollbar:     #2a2d3a;
      --send-bg:       #5b7fff;
      --send-hover:    #7a99ff;
      --shadow:        0 8px 40px rgba(0,0,0,0.5);
      --radius:        14px;
      --transition:    0.22s cubic-bezier(0.4,0,0.2,1);
    }

    [data-theme="light"] {
      --bg-base:       #f4f5f9;
      --bg-sidebar:    #ffffff;
      --bg-chat:       #f4f5f9;
      --bg-input:      #ffffff;
      --bg-user-msg:   #e8edff;
      --bg-ai-msg:     #ffffff;
      --border:        rgba(0,0,0,0.08);
      --text-primary:  #181a26;
      --text-secondary:#5a5f7a;
      --text-muted:    #a0a4b8;
      --tag-bg:        rgba(91,127,255,0.1);
      --scrollbar:     #d0d3e0;
      --shadow:        0 8px 40px rgba(0,0,0,0.08);
    }

    html, body { height: 100%; font-family: Poppins, Helvetica, "sans-serif"; background: var(--bg-base); color: var(--text-primary); transition: background var(--transition), color var(--transition); }

    /* ── Layout ─────────────────────────────────── */
    .app {
      display: flex;
      height: 100vh;
      overflow: hidden;
      position: relative;
      height: 100dvh;
    }

    /* ── Sidebar ─────────────────────────────────── */
    .sidebar {
      width: 280px;
      min-width: 280px;
      background: var(--bg-sidebar);
      border-right: 1px solid var(--border);
      display: flex;
      flex-direction: column;
      padding: 0;
      transition: background var(--transition);
      position: relative;
      z-index: 10;
      transition: all 0.35s ease-in-out;
    }

    .sidebar-header {
      padding: 24px 20px 16px;
      border-bottom: 1px solid var(--border);
      transition: all 0.35s ease-in-out;
    }

    .logo {
      font-weight: bold;
      font-size: 1.3rem;
      letter-spacing: -0.5px;
      color: var(--text-primary);
      text-transform: uppercase;
      display: flex;
      align-items: center;
      gap: 10px;
      margin-bottom: 18px;
      transition: all 0.35s ease-in-out;
    }

    .logo-icon {
      width: 32px; height: 32px;min-width: 32px;
      background: linear-gradient(135deg, #5b7fff, #a78bfa);
      border-radius: 9px;
      display: flex; align-items: center; justify-content: center;
      font-size: 0.9rem;
      color: #ffffff;
      box-shadow: 0 0 18px var(--accent-glow);
    }

    /* Dark/Light Toggle */
    .theme-row {
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .theme-label {
      font-size: 0.78rem;
      font-weight: 500;
      color: var(--text-secondary);
      letter-spacing: 0.5px;
      text-transform: uppercase;
    }

    .toggle-switch {
      position: relative;
      width: 46px; height: 24px;
      cursor: pointer;
    }

    .toggle-switch input { opacity: 0; width: 0; height: 0; }

    .toggle-track {
      position: absolute; inset: 0;
      background: var(--bg-input);
      border: 1px solid var(--border);
      border-radius: 99px;
      transition: background var(--transition);
    }

    .toggle-track::after {
      content: '';
      position: absolute;
      top: 3px; left: 3px;
      width: 16px; height: 16px;
      background: var(--accent);
      border-radius: 50%;
      transition: transform 0.25s cubic-bezier(0.4,0,0.2,1), background var(--transition);
      box-shadow: 0 0 8px var(--accent-glow);
    }

    .toggle-switch input:checked + .toggle-track::after {
      transform: translateX(22px);
    }

    .toggle-icons {
      position: absolute;
      inset: 0;
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0 5px;
      pointer-events: none;
      font-size: 0.6rem;
    }

    /* Prompt input in sidebar */
    .sidebar-prompt {
      padding: 16px 20px;
      border-bottom: 1px solid var(--border);
    }

    .sidebar-prompt label {
      font-size: 0.72rem;
      font-weight: 600;
      color: var(--text-muted);
      letter-spacing: 0.8px;
      text-transform: uppercase;
      display: block;
      margin-bottom: 8px;
    }

    .sidebar-input-wrap {
      display: flex;
      gap: 6px;
    }

    .sidebar-input {
      flex: 1;
      background: var(--bg-input);
      border: 1px solid var(--border);
      border-radius: 10px;
      color: var(--text-primary);
      font-size: 0.82rem;
      padding: 9px 12px;
      outline: none;
      transition: border-color var(--transition), box-shadow var(--transition);
    }

    .sidebar-input:focus {
      border-color: var(--accent);
      box-shadow: 0 0 0 3px var(--accent-soft);
    }

    .sidebar-input::placeholder { color: var(--text-muted); }

    .sidebar-send-btn {
      width: 36px; height: 36px;
      background: var(--accent);
      border: none;
      border-radius: 10px;
      color: #fff;
      cursor: pointer;
      display: flex; align-items: center; justify-content: center;
      font-size: 0.85rem;
      transition: background var(--transition), transform 0.15s;
      flex-shrink: 0;
    }

    .sidebar-send-btn:hover { background: var(--send-hover); transform: scale(1.06); }

    /* Prompt History */
    .sidebar-history {
      flex: 1;
      overflow-y: auto;
      padding: 14px 20px;
    }

    .history-title {
      font-size: 0.72rem;
      font-weight: 600;
      color: var(--text-muted);
      letter-spacing: 0.8px;
      text-transform: uppercase;
      margin-bottom: 10px;
    }

    .history-item {
      display: flex;
      align-items: center;
      gap: 10px;
      padding: 9px 11px;
      border-radius: 9px;
      cursor: pointer;
      transition: background var(--transition);
      margin-bottom: 4px;
      border: 1px solid transparent;
    }

    .history-item:hover {
      background: var(--accent-soft);
      border-color: var(--border);
    }

    .history-item.active {
      background: var(--accent);
      border-color: rgba(91,127,255,0.3);
    }
    .history-item i {
      width: 16px;
    }
    .history-item.active .history-text,
    .history-item.active i {
      color: #ffffff;
    }

    .history-dot {
      width: 6px; height: 6px;
      border-radius: 50%;
      background: var(--accent);
      flex-shrink: 0;
      opacity: 0.7;
    }

    .history-text {
      font-size: 0.82rem;
      color: var(--text-secondary);
      white-space: nowrap;
      overflow: hidden;
      text-overflow: ellipsis;
      line-height: 1.3;
    }

    /* Scrollbar styling */
    .sidebar-history::-webkit-scrollbar { width: 4px; }
    .sidebar-history::-webkit-scrollbar-track { background: transparent; }
    .sidebar-history::-webkit-scrollbar-thumb { background: var(--scrollbar); border-radius: 99px; }

    /* ── Main Chat Area ───────────────────────────── */
    .chat-wrapper {
      flex: 1;
      display: flex;
      flex-direction: column;
      overflow: hidden;
      position: relative;
    }

    /* Top bar */
    .topbar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 16px 28px;
      border-bottom: 1px solid var(--border);
      background: var(--bg-chat);
      backdrop-filter: blur(10px);
      -webkit-backdrop-filter: blur(10px);
      flex-shrink: 0;
    }

    .topbar-title {
      font-weight: 700;
      font-size: 1rem;
      color: var(--text-primary);
      letter-spacing: -0.3px;
    }

    .topbar-status {
      display: flex;
      align-items: center;
      gap: 7px;
      font-size: 0.78rem;
      color: var(--text-secondary);
    }

    .status-dot {
      width: 7px; height: 7px;
      border-radius: 50%;
      background: #4ade80;
      box-shadow: 0 0 7px rgba(74,222,128,0.7);
      animation: pulse 2s ease-in-out infinite;
    }

    @keyframes pulse {
      0%, 100% { opacity: 1; }
      50% { opacity: 0.4; }
    }

    .model-badge {
      background: var(--tag-bg);
      border: 1px solid rgba(91,127,255,0.25);
      color: var(--accent);
      font-size: 0.72rem;
      font-weight: 600;
      padding: 3px 10px;
      border-radius: 99px;
      letter-spacing: 0.3px;
    }

    /* Chat messages */
    .chat-messages {
      flex: 1;
      overflow-y: auto;
      padding: 28px 0;
      scroll-behavior: smooth;
    }

    .chat-messages::-webkit-scrollbar { width: 5px; }
    .chat-messages::-webkit-scrollbar-track { background: transparent; }
    .chat-messages::-webkit-scrollbar-thumb { background: var(--scrollbar); border-radius: 99px; }

    .message-row {
      display: flex;
      gap: 14px;
      padding: 6px 28px;
      max-width: 1000px;
      margin: 0 auto;
      width: 100%;
      animation: fadeUp 0.3s cubic-bezier(0.4,0,0.2,1);
    }

    @keyframes fadeUp {
      from { opacity: 0; transform: translateY(12px); }
      to   { opacity: 1; transform: translateY(0); }
    }

    .message-row.user { flex-direction: row-reverse; }

    .avatar {
      width: 34px; height: 34px;
      border-radius: 10px;
      flex-shrink: 0;
      display: flex; align-items: center; justify-content: center;
      font-size: 0.85rem;
      font-weight: 700;
      margin-top: 2px;
    }

    .avatar.ai {
      background: linear-gradient(135deg, #5b7fff, #a78bfa);
      color: #fff;
      box-shadow: 0 0 16px var(--accent-glow);
    }

    .avatar.user {
      background: var(--bg-user-msg);
      border: 1px solid var(--border);
      color: var(--accent);
    }

    .bubble-wrap { display: flex; flex-direction: column; gap: 4px; max-width: 75%; }
    .message-row.user .bubble-wrap { align-items: flex-end; }

    .sender-name {
      font-size: 0.72rem;
      font-weight: 600;
      color: var(--text-muted);
      letter-spacing: 0.4px;
      text-transform: uppercase;
      padding: 0 4px;
    }

    .bubble {
      padding: 10px 15px;
      border-radius: var(--radius);
      font-size: 0.85rem;
      line-height: 1.2;
      color: var(--text-primary);
      word-break: break-word;
      position: relative;
      transition: background var(--transition);
    }

    .bubble.ai {
      background: var(--bg-ai-msg);
      border: 1px solid var(--border);
      border-top-left-radius: 4px;
    }

    .bubble.ai ul,
    .bubble-main ul,
    .bubble.ai ol,
    .bubble-main ol{
      padding-left: 28px !important;
      margin-bottom: 24px !important;
    }

    .bubble li{
      font-size: 13px;
    }

    .bubble-main p{
      font-size: 14px;
      line-height: normal;
      font-weight: 600;
      margin-bottom: 10px;
    }
    .bubble-main p:last-child{margin-bottom: 0;}
    .bubble-main ul li p,
    .bubble-main ol li p {
      font-size: 14px;
      font-weight: normal;
    }

    .bubble.user {
      background: var(--bg-user-msg);
      border: 1px solid rgba(91,127,255,0.2);
      border-top-right-radius: 4px;
    }

    /* Searched files block */
    .searched-files-block {
      background: var(--bg-ai-msg);
      border: 1px solid var(--border);
      border-radius: var(--radius);
      padding: 12px 16px;
      margin-bottom: 6px;
    }

    .searched-files-header {
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 0.78rem;
      color: var(--text-muted);
      font-weight: 500;
      margin-bottom: 8px;
    }

    .searched-files-header svg { opacity: 0.6; }

    .file-tag {
      display: inline-flex;
      align-items: center;
      background: var(--tag-bg);
      border: 1px solid rgba(91,127,255,0.2);
      color: var(--accent);
      font-size: 0.75rem;
      padding: 3px 9px;
      border-radius: 6px;
      margin: 2px;
    }

    /* Result card */
    .result-card {
      background: var(--bg-ai-msg);
      border: 1px solid var(--border);
      border-radius: var(--radius);
      padding: 14px 16px;
      margin-bottom: 6px;
    }

    .result-num {
      font-size: 0.7rem;
      font-weight: 700;
      color: var(--accent);
      letter-spacing: 0.5px;
      text-transform: uppercase;
      margin-bottom: 6px;
    }

    .result-title {
      font-weight: 600;
      font-size: 0.88rem;
      color: var(--text-primary);
      margin-bottom: 6px;
    }

    .result-field {
      font-size: 0.8rem;
      color: var(--text-secondary);
      margin: 2px 0;
      display: flex;
      gap: 8px;
    }

    .result-field span:first-child { color: var(--text-muted); min-width: 90px; }

    /* Thinking label */
    .thinking-label {
      font-size: 0.75rem;
      color: var(--text-muted);
      font-style: italic;
      padding: 0 4px;
      display: flex;
      align-items: center;
      gap: 6px;
    }

    .thinking-dots span {
      display: inline-block;
      width: 4px; height: 4px;
      background: var(--text-muted);
      border-radius: 50%;
      animation: blink 1.4s ease-in-out infinite;
    }
    .thinking-dots span:nth-child(2) { animation-delay: 0.2s; }
    .thinking-dots span:nth-child(3) { animation-delay: 0.4s; }

    @keyframes blink {
      0%, 80%, 100% { opacity: 0.2; transform: scale(0.8); }
      40% { opacity: 1; transform: scale(1); }
    }

    /* ── Chat Input ───────────────────────────────── */
    .chat-input-area {
      padding: 16px 28px 20px;
      border-top: 1px solid var(--border);
      background: var(--bg-chat);
      flex-shrink: 0;
    }

    .input-inner {
      max-width: 860px;
      margin: 0 auto;
      display: flex;
      align-items: center;
      gap: 10px;
      background: var(--bg-input);
      border: 1px solid var(--border);
      border-radius: 16px;
      padding: 10px 10px 10px 18px;
      transition: border-color var(--transition), box-shadow var(--transition);
    }

    .input-inner:focus-within {
      border-color: var(--accent);
      box-shadow: 0 0 0 3px var(--accent-soft);
    }

    #chat-input {
      flex: 1;
      background: transparent;
      border: none;
      outline: none;
      color: var(--text-primary);
      font-size: 0.92rem;
      line-height: 1.5;
      resize: none;
      max-height: 160px;
      overflow-y: auto;
    }

    #chat-input::placeholder { color: var(--text-muted); }

    #chat-input::-webkit-scrollbar { width: 3px; }
    #chat-input::-webkit-scrollbar-thumb { background: var(--scrollbar); border-radius: 99px; }

    .send-btn {
      width: 40px; height: 40px;
      background: var(--send-bg);
      border: none;
      border-radius: 11px;
      color: #fff;
      cursor: pointer;
      display: flex; align-items: center; justify-content: center;
      font-size: 1rem;
      transition: background var(--transition), transform 0.15s, box-shadow var(--transition);
      flex-shrink: 0;
      box-shadow: 0 2px 12px var(--accent-glow);
    }

    .send-btn:hover { background: var(--send-hover); transform: scale(1.07); box-shadow: 0 4px 20px var(--accent-glow); }
    .send-btn:active { transform: scale(0.96); }

    .new-chat-btn {
      width: 100px; height: 40px;
      background: var(--send-bg);
      border: none;
      border-radius: 11px;
      color: #fff;
      cursor: pointer;
      display: flex; align-items: center; justify-content: center;
      font-size: 1rem;
      transition: background var(--transition), transform 0.15s, box-shadow var(--transition);
      flex-shrink: 0;
      box-shadow: 0 2px 12px var(--accent-glow);
    }

    .new-chat-btn:hover { background: var(--send-hover); transform: scale(1.07); box-shadow: 0 4px 20px var(--accent-glow); }
    .new-chat-btn:active { transform: scale(0.96); }

    .input-hint {
      max-width: 860px;
      margin: 8px auto 0;
      font-size: 0.72rem;
      color: var(--text-muted);
      text-align: center;
    }

    /* Empty state */
    .empty-state {
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      height: 100%;
      gap: 14px;
      padding: 40px;
      text-align: center;
    }

    .empty-icon {
      width: 56px; height: 56px;
      background: linear-gradient(135deg, #5b7fff, #a78bfa);
      border-radius: 18px;
      display: flex; align-items: center; justify-content: center;
      font-size: 1.5rem;
      box-shadow: 0 0 30px var(--accent-glow);
      margin-bottom: 4px;
    }

    .empty-state h2 {
      font-size: 1.1rem;
      font-weight: 700;
      color: var(--text-primary);
    }

    .empty-state p {
      font-size: 0.85rem;
      color: var(--text-secondary);
      max-width: 300px;
    }

    /* Separator */
    .msg-separator {
      text-align: center;
      font-size: 0.7rem;
      color: var(--text-muted);
      margin: 10px 28px;
      display: flex;
      align-items: center;
      gap: 10px;
      max-width: 860px;
      margin-left: auto;
      margin-right: auto;
    }
    .msg-separator::before, .msg-separator::after {
      content: '';
      flex: 1;
      height: 1px;
      background: var(--border);
    }

    /* ── Mobile Menu Button ───────────────────────── */
    .menu-btn {
      display: none;
      align-items: center; justify-content: center;
      width: 36px; height: 36px;
      background: var(--bg-input);
      border: 1px solid var(--border);
      border-radius: 9px;
      cursor: pointer;
      color: var(--text-primary);
      transition: background var(--transition);
      flex-shrink: 0;
    }
    .menu-btn:hover { background: var(--accent-soft); }

    /* Overlay backdrop */
    .sidebar-overlay {
      display: none;
      position: fixed; inset: 0;
      background: rgba(0,0,0,0.55);
      z-index: 98;
      backdrop-filter: blur(2px);
      -webkit-backdrop-filter: blur(2px);
      opacity: 0;
      transition: opacity 0.3s ease;
      pointer-events: none;
    }
    .sidebar-overlay.active {
      opacity: 1;
      pointer-events: all;
    }
    .bubble ul {
      padding-left: 20px;
      margin-top: 8px;
    }
    .bubble hr {
        margin-bottom: 15px;
    }
     .bubble table {
      width: 100%;
      border-collapse: collapse;
      margin: 15px 0;
    }

     .bubble table, .bubble table th, .bubble table td {
      border: 1px solid #ccc;
    }

    .bubble table th, .bubble table td {
      padding: 8px;
      text-align: left;
    }
    .bubble li:not(:last-child) {
      margin-bottom:15px;
    }
    
    .send-btn:disabled, .new-chat-btn:disabled {
      cursor: not-allowed;
      opacity: 0.5;        
      box-shadow: none;  
    }

    .send-btn:enabled, .new-chat-btn:enabled {
      cursor: pointer;    
      opacity: 1;
    }
    
    .separator {
      border: none;           
      border-top: 1px solid var(--border);  
      margin: 5px 0;          
    }
    /* Close button inside sidebar (mobile) */
    .sidebar-close {
      display: none;
      align-items: center; justify-content: center;
      width: 30px; height: 30px;
      background: var(--bg-input);
      border: 1px solid var(--border);
      border-radius: 8px;
      cursor: pointer;
      color: var(--text-secondary);
      font-size: 1rem;
      line-height: 1;
      margin-left: auto;
      transition: background var(--transition), color var(--transition);
    }
    .sidebar-close:hover { background: var(--accent-soft); color: var(--accent); }

    .pdf-upload-btn {
        display: inline-flex;
        align-items: center;
        justify-content: center;
        cursor: pointer;
        margin-right: 8px;
    }
    .pdf-upload-btn svg {
      width: 22px;
      height: 22px;
    }
    .pdf-upload-btn svg path{
      fill: var(--text-primary);
    }
    .pdf-upload-btn.disabled-upload-icon{cursor: not-allowed;}
 
    .uploaded-image {
        max-width: 200px;
        max-height: 200px;
        border-radius: 8px;
    }

    .file-chip {
        display: inline-flex;
        align-items: center;
        background: #fffefe;
        padding: 6px 10px;
        border-radius: 8px;
        margin-bottom: 6px;
        font-size: 13px;
        gap: 6px;
    }

    .remove-file {
        cursor: pointer;
        margin-left: 8px;
    }
    /* Sidebar Search Style */
    .sidebar-search {
      padding: 8px;
    }

    #search-input {
      width: 100%;
      padding: 10px;
      border-radius: 8px;
      font-size: 0.92rem;
      line-height: 1.5;
      background: var(--bg-input);
      border: 1px solid var(--border);
      outline: none;
      color: var(--text-primary);
  }
  #search-input:focus { border-color: var(--send-bg)}
  #search-input::placeholder { color: var(--text-muted); }
  /**/

    .sidebar-toggle {
        width: 32px;
        height: 32px;
        position: absolute;
        cursor: pointer;
        transform: rotate(0deg);
        transition: .3s ease-in-out;
        background: var(--bg-input);
        border: 1px solid var(--border);
        padding: 8px;
        box-sizing: border-box;
        right: 20px;
        border-radius: 4px;
    }

    .sidebar-toggle span {
        position: absolute;
        height: 2px;
        width: 20px;
        background: var(--text-primary);
        border-radius: 4px;
        transform: rotate(0deg);
        transition: .20s ease-in-out;
        left: 5px;
    }

    .sidebar-toggle.open span:nth-child(1) {
      top: 13px;
      transform: rotate(135deg);
    }

    .sidebar-toggle.open span:nth-child(2) {
      opacity: 0;
    }

    .sidebar-toggle.open span:nth-child(3) {
      top: 13px;
      transform: rotate(-135deg);
    }

    .sidebar-toggle span:nth-child(1) {
        top: 8px;
    }

    .sidebar-toggle span:nth-child(2) {
        top: 14px;
    }

    .sidebar-toggle span:nth-child(3) {
      top: 20px;
    }
    .sidebar.select {
        width: 52px;
        min-width: 52px;
        transition: all 0.35s ease-in-out;
    }
    .sidebar.select .sidebar-header {
        padding: 24px 8px 16px;
    }
    .sidebar.select .sidebar-header .logo,
    .sidebar.select .theme-row .theme-label {
        font-size: 0;
        margin-bottom: 0;
    }
    .sidebar.select .sidebar-header .sidebar-toggle{
      right: auto;
      opacity: 0;
    }
    .sidebar.select .sidebar-header .sidebar-toggle:hover{
      opacity:1;
    }
    .sidebar.select .theme-row{
      display: none;
    }
    .sidebar.select .sidebar-history {
        display: none;
    }
    
    #file-preview {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 10px;

      background: #f5f7fb;
      border: 1px solid #e3e6ef;
      border-radius: 10px;

      padding: 6px 10px;
      margin-top: 6px;

      max-width: 100%;
      font-size: 13px;
      color: #333;
    }

    #file-name {
      display: flex;
      align-items: center;
      gap: 6px;

      overflow: hidden;
      white-space: nowrap;
      text-overflow: ellipsis;

      flex: 1;
    }

    #remove-file {
      border: none;
      background: transparent;
      color: #888;

      font-size: 16px;
      cursor: pointer;

      width: 24px;
      height: 24px;

      display: flex;
      align-items: center;
      justify-content: center;

      border-radius: 50%;
      transition: all 0.2s ease;
    }

    #remove-file:hover {
      background: #e4e7f2;
      color: #333;
    }

    #remove-file:active {
      transform: scale(0.9);
    }
    .download-btn {
      width: 32px; height: 32px;
      background: var(--send-bg);
      border: none;
      border-radius: 11px;
      color: #fff;
      cursor: pointer;
      display: flex; align-items: center; justify-content: center;
      font-size: 1rem;
      transition: background var(--transition), transform 0.15s, box-shadow var(--transition);
      flex-shrink: 0;
      box-shadow: 0 2px 12px var(--accent-glow);
      margin-left: auto;
      margin-top: 5px;
    }
    .download-btn svg{width: 20px; height: 20px;}

    .download-btn:hover { background: var(--send-hover); transform: scale(1.07); box-shadow: 0 4px 20px var(--accent-glow); }
    #file-name svg,
    .bubble.user > svg{
      width: 24px;
      height: 24px;
      vertical-align: middle;
    }
    /* ── Tablet (≤900px) ─────────────────────────── */
    @media (max-width: 900px) {
      .sidebar {
        width: 260px;
        min-width: 260px;
      }
      .message-row { padding: 6px 18px; }
      .topbar { padding: 14px 18px; }
      .chat-input-area { padding: 12px 18px 16px; }
      .logo { font-size: 1.1rem; }
    }

    /* ── Mobile (≤680px) ─────────────────────────── */
    @media (max-width: 680px) {
      /* Show hamburger */
      .menu-btn { display: flex; }

      /* Sidebar becomes a drawer */
      .sidebar {
        position: fixed;
        top: 0; left: 0; bottom: 0;
        width: 290px;
        min-width: unset;
        z-index: 99;
        transform: translateX(-100%);
        transition: transform 0.32s cubic-bezier(0.4,0,0.2,1), background var(--transition);
       
      }

      .sidebar.open { transform: translateX(0); box-shadow: 4px 0 40px rgba(0,0,0,0.4); }

      /* Show overlay when sidebar open */
      .sidebar-overlay { display: block; pointer-events: none; }

      /* Show close button */
      .sidebar-close { display: flex; }

      /* Adjust logo row to fit close button */
      .logo { margin-bottom: 10px; }

      .topbar { padding: 12px 14px; gap: 8px; }
      .topbar-title { font-size: 0.9rem; }
      .model-badge { display: none; }

      .message-row { padding: 5px 12px; }
      .bubble-wrap { max-width: 88%; }
      .bubble { font-size: 0.85rem; padding: 11px 14px; }

      .chat-input-area { padding: 10px 12px 14px; }
      .input-inner { border-radius: 13px; padding: 8px 8px 8px 14px; }
      #chat-input { font-size: 0.88rem; }
      .send-btn { width: 36px; height: 36px; border-radius: 9px; }

      .input-hint { font-size: 0.68rem; }

      .result-field { flex-direction: column; gap: 2px; }
      .result-field span:first-child { min-width: unset; }

      .searched-files-block, .result-card { padding: 10px 12px; }
      .file-tag { font-size: 0.7rem; padding: 2px 7px; }

      .empty-state { padding: 24px 20px; }
      .empty-state h2 { font-size: 1rem; }
      .empty-state p { font-size: 0.8rem; }
      .sidebar .sidebar-toggle{display: none;}
      .new-chat-btn {
        width: 90px;
        height: 36px;
        border-radius: 8px;
    }
    }

    /* ── Small phones (≤380px) ───────────────────── */
    @media (max-width: 380px) {
      .sidebar { width: 100vw; }
      .bubble-wrap { max-width: 94%; }
      .avatar { width: 28px; height: 28px; font-size: 0.75rem; border-radius: 8px; }
      .bubble { font-size: 0.82rem; padding: 10px 12px; }
    }