:root {
      --bg: #f8fafc;
      --surface: #ffffff;
      --surface2: #f1f5f9;
      --border: #e2e8f0;
      --accent: #2563eb;
      --accent-light: #3b82f6;
      --text: #1e293b;
      --text-muted: #64748b;
      --success: #22c55e;
      --warning: #f59e0b;
      --danger: #ef4444;
      --info: #3b82f6;
      --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
      --shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
      --shadow-md: 0 4px 6px rgba(0,0,0,0.07), 0 2px 4px rgba(0,0,0,0.06);
    }

    [data-theme="dark"] {
      --bg: #0f172a;
      --surface: #1e293b;
      --surface2: #334155;
      --border: #334155;
      --accent: #3b82f6;
      --accent-light: #60a5fa;
      --text: #f1f5f9;
      --text-muted: #94a3b8;
      --shadow-sm: 0 1px 2px rgba(0,0,0,0.2);
      --shadow: 0 1px 3px rgba(0,0,0,0.3);
      --shadow-md: 0 4px 6px rgba(0,0,0,0.25);
    }

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

    body {
      font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Inter', system-ui, sans-serif;
      background: var(--bg);
      color: var(--text);
      min-height: 100vh;
      line-height: 1.5;
    }

    /* --- Header --- */
    header {
      padding: 14px 32px;
      border-bottom: 1px solid var(--border);
      display: flex;
      align-items: center;
      gap: 16px;
      background: var(--surface);
      position: sticky;
      top: 0;
      z-index: 10;
      box-shadow: var(--shadow-sm);
    }
    .logo {
      font-size: 20px;
      font-weight: 800;
      letter-spacing: -0.5px;
      color: var(--text);
    }
    .logo span { color: var(--accent); }
    header p {
      color: var(--text-muted);
      font-size: 13px;
    }
    .header-spacer { flex: 1; }
    .header-badge {
      font-size: 11px;
      padding: 4px 12px;
      border-radius: 20px;
      background: rgba(37,99,235,0.08);
      border: 1px solid rgba(37,99,235,0.2);
      color: var(--accent);
      font-weight: 600;
    }
    [data-theme="dark"] .header-badge {
      background: rgba(59,130,246,0.12);
      border-color: rgba(59,130,246,0.25);
    }
    .theme-toggle {
      background: none;
      border: 1px solid var(--border);
      border-radius: 8px;
      padding: 6px;
      cursor: pointer;
      color: var(--text-muted);
      display: flex;
      align-items: center;
      justify-content: center;
      transition: all 0.2s;
    }
    .theme-toggle:hover {
      color: var(--text);
      border-color: var(--text-muted);
    }
    .theme-toggle .material-icons { font-size: 18px; }

    /* --- Main layout --- */
    main {
      max-width: 1200px;
      margin: 0 auto;
      padding: 32px 24px;
    }

    /* --- Upload zone --- */
    .upload-zone {
      border: 2px dashed var(--border);
      border-radius: 16px;
      padding: 56px 40px;
      text-align: center;
      cursor: pointer;
      transition: all 0.2s ease;
      background: var(--surface);
      margin-bottom: 28px;
      box-shadow: var(--shadow-sm);
    }
    .upload-zone:hover, .upload-zone.dragover {
      border-color: var(--accent);
      background: rgba(37,99,235,0.02);
    }
    [data-theme="dark"] .upload-zone:hover,
    [data-theme="dark"] .upload-zone.dragover {
      background: rgba(59,130,246,0.04);
    }
    .upload-zone.dragover { border-style: solid; }
    .upload-icon {
      font-size: 48px;
      margin-bottom: 12px;
      color: var(--accent);
      opacity: 0.6;
    }
    .upload-title { font-size: 18px; font-weight: 700; margin-bottom: 6px; }
    .upload-sub { color: var(--text-muted); font-size: 14px; }
    #fileInput { display: none; }

    /* --- Content grid --- */
    .content-grid {
      display: grid;
      grid-template-columns: 300px 1fr;
      gap: 20px;
    }
    .batch-panel {
      grid-column: 1 / -1;
      background: var(--surface);
      border: 1px solid var(--border);
      border-radius: 12px;
      padding: 16px;
      display: flex;
      flex-direction: column;
      gap: 14px;
      box-shadow: var(--shadow-sm);
    }
    .batch-panel-head {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 12px;
      flex-wrap: wrap;
    }
    .batch-title-wrap {
      display: flex;
      flex-direction: column;
      gap: 2px;
    }
    .batch-title { font-size: 14px; font-weight: 700; }
    .batch-sub { color: var(--text-muted); font-size: 12px; }
    .batch-pill {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      min-width: 28px;
      padding: 2px 10px;
      border-radius: 999px;
      background: rgba(37,99,235,0.08);
      border: 1px solid rgba(37,99,235,0.2);
      color: var(--accent);
      font-size: 11px;
      font-weight: 700;
    }
    [data-theme="dark"] .batch-pill {
      background: rgba(59,130,246,0.12);
      border-color: rgba(59,130,246,0.25);
    }
    .batch-strip {
      display: grid;
      grid-template-columns: repeat(auto-fill, minmax(110px, 1fr));
      gap: 10px;
    }
    .batch-item {
      border: 1px solid var(--border);
      border-radius: 10px;
      background: var(--surface2);
      overflow: hidden;
      cursor: pointer;
      transition: border-color 0.15s, transform 0.15s, box-shadow 0.15s;
    }
    .batch-item:hover {
      border-color: var(--accent);
      transform: translateY(-1px);
      box-shadow: var(--shadow);
    }
    .batch-item.active {
      border-color: var(--accent);
      box-shadow: 0 0 0 2px rgba(37,99,235,0.15);
    }
    [data-theme="dark"] .batch-item.active {
      box-shadow: 0 0 0 2px rgba(59,130,246,0.2);
    }
    .batch-thumb {
      width: 100%;
      aspect-ratio: 1;
      background: var(--surface2);
      display: block;
      object-fit: cover;
    }
    .batch-thumb-empty {
      width: 100%;
      aspect-ratio: 1;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--text-muted);
      font-size: 24px;
      background: var(--surface2);
    }
    .batch-item-body {
      padding: 8px 10px;
      display: flex;
      flex-direction: column;
      gap: 6px;
    }
    .batch-item-name {
      font-size: 11px;
      font-weight: 600;
      line-height: 1.3;
      min-height: 28px;
      word-break: break-word;
    }
    .batch-status {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 6px;
      font-size: 11px;
    }
    .batch-status-tag {
      padding: 2px 7px;
      border-radius: 999px;
      border: 1px solid var(--border);
      color: var(--text-muted);
      background: var(--surface);
      font-weight: 600;
      white-space: nowrap;
      font-size: 10px;
    }
    .batch-status-tag.ready {
      color: var(--success);
      border-color: rgba(34,197,94,0.3);
      background: rgba(34,197,94,0.06);
    }
    .batch-status-tag.processing {
      color: var(--warning);
      border-color: rgba(245,158,11,0.3);
      background: rgba(245,158,11,0.06);
    }
    .batch-status-tag.error {
      color: var(--danger);
      border-color: rgba(239,68,68,0.3);
      background: rgba(239,68,68,0.06);
    }
    .batch-status-meta {
      color: var(--text-muted);
      font-size: 10px;
      white-space: nowrap;
    }

    /* --- Left panel --- */
    .left-panel {
      display: flex;
      flex-direction: column;
      gap: 16px;
    }
    .preview-card {
      background: var(--surface);
      border: 1px solid var(--border);
      border-radius: 12px;
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }
    .preview-img-wrap {
      width: 100%;
      aspect-ratio: 1;
      background: var(--surface2);
      overflow: hidden;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    #previewImg {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
    }
    .preview-info {
      padding: 12px 14px;
      border-top: 1px solid var(--border);
    }
    .preview-name {
      font-size: 13px;
      font-weight: 600;
      white-space: nowrap;
      overflow: hidden;
      text-overflow: ellipsis;
      margin-bottom: 2px;
    }
    .preview-meta { color: var(--text-muted); font-size: 12px; }

    /* --- Action card --- */
    .action-card {
      background: var(--surface);
      border: 1px solid var(--border);
      border-radius: 12px;
      padding: 14px;
      display: flex;
      flex-direction: column;
      gap: 8px;
      box-shadow: var(--shadow-sm);
    }
    .action-card-title {
      font-size: 11px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.08em;
      color: var(--text-muted);
      margin-bottom: 2px;
    }
    .option-row {
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 13px;
      cursor: pointer;
      padding: 2px 0 6px;
      color: var(--text);
    }
    .option-row input[type="checkbox"] {
      width: 16px;
      height: 16px;
      accent-color: var(--accent);
      cursor: pointer;
    }

    /* --- Buttons --- */
    .btn {
      width: 100%;
      padding: 10px 14px;
      border-radius: 8px;
      border: none;
      cursor: pointer;
      font-size: 13px;
      font-weight: 600;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
      transition: all 0.15s;
    }
    .btn-primary {
      background: var(--accent);
      color: white;
    }
    .btn-primary:hover:not(:disabled) { opacity: 0.9; }
    .btn-secondary {
      background: var(--surface2);
      color: var(--text);
      border: 1px solid var(--border);
    }
    .btn-secondary:hover:not(:disabled) { border-color: var(--accent); color: var(--accent); }
    .btn-danger {
      background: rgba(239,68,68,0.06);
      color: var(--danger);
      border: 1px solid rgba(239,68,68,0.2);
    }
    .btn-danger:hover:not(:disabled) { background: rgba(239,68,68,0.12); }
    .btn-success {
      background: rgba(34,197,94,0.06);
      color: var(--success);
      border: 1px solid rgba(34,197,94,0.2);
    }
    .btn-success:hover:not(:disabled) { background: rgba(34,197,94,0.12); }
    .btn:disabled { opacity: 0.4; cursor: not-allowed; }

    /* --- Right panel (metadata) --- */
    .meta-panel {
      background: var(--surface);
      border: 1px solid var(--border);
      border-radius: 12px;
      overflow: hidden;
      display: flex;
      flex-direction: column;
      box-shadow: var(--shadow-sm);
    }
    .meta-topbar {
      padding: 12px 18px;
      border-bottom: 1px solid var(--border);
      display: flex;
      align-items: center;
      justify-content: space-between;
    }
    .meta-topbar-title { font-size: 15px; font-weight: 700; }
    .badge {
      padding: 3px 10px;
      border-radius: 20px;
      font-size: 11px;
      font-weight: 700;
      letter-spacing: 0.03em;
    }
    .badge-original { background: rgba(34,197,94,0.1);  color: var(--success); }
    .badge-fake     { background: rgba(59,130,246,0.1);  color: var(--accent); }
    .badge-cleared  { background: rgba(239,68,68,0.1);   color: var(--danger); }
    .badge-none     { background: rgba(100,116,139,0.1); color: var(--text-muted); }

    /* Tabs */
    .meta-tabs {
      display: flex;
      border-bottom: 1px solid var(--border);
      background: var(--surface);
    }
    .tab {
      flex: 1;
      padding: 10px 16px;
      font-size: 13px;
      font-weight: 600;
      cursor: pointer;
      color: var(--text-muted);
      border-bottom: 2px solid transparent;
      text-align: center;
      transition: all 0.15s;
    }
    .tab:hover { color: var(--text); }
    .tab.active { color: var(--accent); border-bottom-color: var(--accent); }
    .tab-count {
      display: inline-block;
      margin-left: 5px;
      padding: 1px 6px;
      border-radius: 10px;
      font-size: 10px;
      background: var(--surface2);
      color: var(--text-muted);
    }
    .tab.active .tab-count { background: rgba(37,99,235,0.1); color: var(--accent); }
    [data-theme="dark"] .tab.active .tab-count { background: rgba(59,130,246,0.15); color: var(--accent-light); }

    /* Metadata body */
    .meta-body {
      flex: 1;
      overflow-y: auto;
      height: 560px;
    }
    .meta-section { padding: 12px 18px 6px; }
    .meta-section-title {
      font-size: 10px;
      font-weight: 800;
      text-transform: uppercase;
      letter-spacing: 0.1em;
      color: var(--text-muted);
      margin-bottom: 8px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .meta-section-title::after {
      content: '';
      flex: 1;
      height: 1px;
      background: var(--border);
    }
    .meta-row {
      display: grid;
      grid-template-columns: 155px 1fr;
      gap: 8px;
      padding: 5px 0;
      border-bottom: 1px solid var(--border);
      align-items: baseline;
    }
    .meta-row:last-child { border-bottom: none; }
    .meta-key  { color: var(--text-muted); font-size: 12px; line-height: 1.4; }
    .meta-val  { font-size: 13px; font-weight: 500; word-break: break-all; line-height: 1.4; }
    .meta-val.is-new { color: var(--accent); }
    .meta-val.is-new::before {
      content: 'NEW ';
      font-size: 8px;
      opacity: 0.7;
      vertical-align: middle;
    }

    .gps-link {
      display: inline-block;
      margin-left: 8px;
      color: var(--info);
      font-size: 11px;
      text-decoration: none;
      opacity: 0.8;
    }
    .gps-link:hover { opacity: 1; text-decoration: underline; }

    .no-meta {
      padding: 48px 24px;
      text-align: center;
      color: var(--text-muted);
    }
    .no-meta-icon { font-size: 36px; margin-bottom: 10px; opacity: 0.3; }
    .no-meta p { font-size: 14px; }

    .changed-from {
      font-size: 11px;
      color: var(--text-muted);
      text-decoration: line-through;
      margin-left: 6px;
    }

    /* --- Responsive --- */
    @media (max-width: 800px) {
      body { overscroll-behavior-y: contain; }
      header { padding: 12px 16px; flex-wrap: wrap; }
      header p { width: 100%; order: 3; font-size: 12px; }
      .header-badge { margin-left: auto; }
      main { padding: 16px 12px; }
      .upload-zone { padding: 36px 16px; border-radius: 14px; }
      .upload-title { font-size: 17px; }
      .content-grid { grid-template-columns: 1fr; }
      .batch-strip { grid-template-columns: repeat(auto-fill, minmax(90px, 1fr)); gap: 8px; }
      .preview-card, .action-card, .meta-panel { border-radius: 10px; }
      .meta-topbar { padding: 10px 14px; }
      .meta-tabs { overflow-x: auto; }
      .tab { min-width: 100px; padding: 10px 12px; }
      .meta-body { height: auto; min-height: 300px; }
      .meta-section { padding: 12px; }
      .meta-row { grid-template-columns: 1fr; gap: 2px; }
      #toast { right: 12px; left: 12px; bottom: 14px; max-width: none; }
    }

    /* --- Scrollbar --- */
    ::-webkit-scrollbar { width: 5px; }
    ::-webkit-scrollbar-track { background: transparent; }
    ::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }

    /* --- Toast --- */
    #toast {
      position: fixed;
      bottom: 24px;
      right: 24px;
      padding: 12px 18px;
      border-radius: 10px;
      font-size: 13px;
      font-weight: 600;
      z-index: 999;
      transform: translateY(80px);
      opacity: 0;
      transition: all 0.3s ease;
      max-width: 340px;
    }
    #toast.show { transform: translateY(0); opacity: 1; }
    #toast.toast-success { background: #f0fdf4; border: 1px solid rgba(34,197,94,0.3);  color: #166534; }
    #toast.toast-info    { background: #eff6ff; border: 1px solid rgba(59,130,246,0.3);  color: #1e40af; }
    #toast.toast-error   { background: #fef2f2; border: 1px solid rgba(239,68,68,0.3);   color: #991b1b; }
    #toast.toast-warning { background: #fffbeb; border: 1px solid rgba(245,158,11,0.3);  color: #92400e; }
    [data-theme="dark"] #toast.toast-success { background: #14532d; color: #86efac; }
    [data-theme="dark"] #toast.toast-info    { background: #1e3a5f; color: #93c5fd; }
    [data-theme="dark"] #toast.toast-error   { background: #451a1a; color: #fca5a5; }
    [data-theme="dark"] #toast.toast-warning { background: #422006; color: #fcd34d; }

    /* --- Spinner --- */
    .spinner {
      display: inline-block;
      width: 14px;
      height: 14px;
      border: 2px solid rgba(0,0,0,0.1);
      border-top-color: var(--accent);
      border-radius: 50%;
      animation: spin 0.7s linear infinite;
    }
    [data-theme="dark"] .spinner { border-color: rgba(255,255,255,0.15); border-top-color: var(--accent-light); }
    @keyframes spin { to { transform: rotate(360deg); } }

    /* --- Footer --- */
    footer {
      text-align: center;
      padding: 24px;
      color: var(--text-muted);
      font-size: 12px;
      border-top: 1px solid var(--border);
      margin-top: 48px;
    }
    footer a { color: var(--accent); text-decoration: none; }
    footer a:hover { text-decoration: underline; }