/* Split mode toggle group */
    .split-mode-group {
      display: flex;
      gap: 0;
      border: 1px solid var(--color-border);
      border-radius: var(--radius-sm);
      overflow: hidden;
      flex-wrap: wrap;
    }
    .split-mode-btn {
      padding: 10px 18px;
      background: var(--color-surface);
      border: none;
      border-right: 1px solid var(--color-border);
      font-family: var(--font-body);
      font-size: 0.82rem;
      font-weight: 600;
      color: var(--color-text-secondary);
      cursor: pointer;
      transition: all var(--transition-fast);
      white-space: nowrap;
    }
    .split-mode-btn:last-child {
      border-right: none;
    }
    .split-mode-btn:hover {
      background: var(--color-surface-hover);
    }
    .split-mode-btn.active {
      background: var(--color-primary-light);
      color: var(--color-primary);
    }

    /* Range input */
    .range-input-wrap {
      display: none;
      margin-top: 12px;
    }
    .range-input-wrap.visible {
      display: block;
    }
    .range-input-wrap input[type="text"] {
      width: 100%;
      padding: 10px 14px;
      border: 1px solid var(--color-border);
      border-radius: var(--radius-sm);
      font-family: var(--font-mono);
      font-size: 0.85rem;
      background: var(--color-surface);
      color: var(--color-text);
      outline: none;
      transition: border-color var(--transition-fast);
    }
    .range-input-wrap input[type="text"]:focus {
      border-color: var(--color-primary);
    }
    .range-input-wrap .hint {
      font-size: 0.75rem;
      color: var(--color-text-muted);
      margin-top: 6px;
    }

    /* Every N input */
    .every-n-wrap {
      display: none;
      margin-top: 12px;
      align-items: center;
      gap: 10px;
    }
    .every-n-wrap.visible {
      display: flex;
    }
    .every-n-wrap label {
      font-size: 0.85rem;
      font-weight: 600;
      color: var(--color-text-secondary);
      white-space: nowrap;
    }
    .every-n-wrap input[type="number"] {
      width: 80px;
      padding: 10px 14px;
      border: 1px solid var(--color-border);
      border-radius: var(--radius-sm);
      font-family: var(--font-mono);
      font-size: 0.85rem;
      background: var(--color-surface);
      color: var(--color-text);
      outline: none;
      transition: border-color var(--transition-fast);
    }
    .every-n-wrap input[type="number"]:focus {
      border-color: var(--color-primary);
    }
    .every-n-wrap .hint {
      font-size: 0.75rem;
      color: var(--color-text-muted);
    }

    /* Page grid */
    .page-grid {
      display: grid;
      grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
      gap: 14px;
      margin-top: 20px;
      padding: 0;
    }
    .page-thumb {
      position: relative;
      border: 2px solid var(--color-border-light);
      border-radius: var(--radius-sm);
      overflow: hidden;
      background: #fff;
      transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
    }
    .page-thumb canvas {
      width: 100%;
      display: block;
    }
    .page-thumb .page-label {
      position: absolute;
      bottom: 0;
      left: 0;
      right: 0;
      padding: 4px 0;
      text-align: center;
      font-size: 0.72rem;
      font-weight: 700;
      color: #fff;
      background: rgba(0,0,0,0.55);
      backdrop-filter: blur(4px);
    }
    .page-thumb .group-badge {
      position: absolute;
      top: 6px;
      right: 6px;
      padding: 2px 7px;
      border-radius: 100px;
      font-size: 0.65rem;
      font-weight: 700;
      color: #fff;
      line-height: 1.4;
    }

    /* Group color palette */
    .group-color-0  { border-color: #6366f1; }
    .group-color-1  { border-color: #06b6d4; }
    .group-color-2  { border-color: #f59e0b; }
    .group-color-3  { border-color: #ef4444; }
    .group-color-4  { border-color: #10b981; }
    .group-color-5  { border-color: #8b5cf6; }
    .group-color-6  { border-color: #ec4899; }
    .group-color-7  { border-color: #14b8a6; }
    .group-color-8  { border-color: #f97316; }
    .group-color-9  { border-color: #3b82f6; }

    .group-bg-0  { background: #6366f1; }
    .group-bg-1  { background: #06b6d4; }
    .group-bg-2  { background: #f59e0b; }
    .group-bg-3  { background: #ef4444; }
    .group-bg-4  { background: #10b981; }
    .group-bg-5  { background: #8b5cf6; }
    .group-bg-6  { background: #ec4899; }
    .group-bg-7  { background: #14b8a6; }
    .group-bg-8  { background: #f97316; }
    .group-bg-9  { background: #3b82f6; }

    /* File info badge */
    .file-info-badge {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      padding: 6px 14px;
      background: var(--color-primary-light);
      color: var(--color-primary);
      border-radius: 100px;
      font-size: 0.8rem;
      font-weight: 600;
      margin-bottom: 12px;
    }

    /* Progress indicator */
    .progress-bar-wrap {
      width: 100%;
      height: 6px;
      background: var(--color-border);
      border-radius: 3px;
      margin-top: 16px;
      overflow: hidden;
      display: none;
    }
    .progress-bar-wrap.visible {
      display: block;
    }
    .progress-bar-fill {
      height: 100%;
      background: var(--color-primary);
      border-radius: 3px;
      transition: width 0.3s ease;
      width: 0%;
    }
    .progress-text {
      text-align: center;
      font-size: 0.8rem;
      color: var(--color-text-muted);
      margin-top: 8px;
      display: none;
    }
    .progress-text.visible {
      display: block;
    }

    /* Results section */
    .results-section {
      display: none;
      margin-top: 24px;
    }
    .results-section.visible {
      display: block;
    }
    .results-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 12px;
      margin-bottom: 16px;
    }
    .results-header h3 {
      margin: 0;
      font-size: 1rem;
      color: var(--color-text);
    }
    .result-item {
      display: flex;
      align-items: center;
      gap: 14px;
      padding: 12px 16px;
      background: var(--color-bg);
      border: 1px solid var(--color-border-light);
      border-radius: var(--radius-sm);
      margin-bottom: 8px;
      transition: all var(--transition-fast);
    }
    .result-item:hover {
      border-color: var(--color-primary-subtle);
      background: var(--color-primary-light);
    }
    .result-icon {
      width: 40px;
      height: 40px;
      display: flex;
      align-items: center;
      justify-content: center;
      background: var(--color-primary-light);
      color: var(--color-primary);
      border-radius: 8px;
      flex-shrink: 0;
      font-size: 1.1rem;
    }
    .result-info {
      flex: 1;
      min-width: 0;
    }
    .result-name {
      font-size: 0.85rem;
      font-weight: 600;
      color: var(--color-text);
      overflow: hidden;
      text-overflow: ellipsis;
      white-space: nowrap;
    }
    .result-meta {
      font-size: 0.72rem;
      color: var(--color-text-muted);
      margin-top: 2px;
      font-family: var(--font-mono);
    }
    .result-download-btn {
      padding: 8px 16px;
      background: var(--color-primary);
      color: #fff;
      border: none;
      border-radius: var(--radius-sm);
      font-family: var(--font-body);
      font-size: 0.8rem;
      font-weight: 600;
      cursor: pointer;
      transition: all var(--transition-fast);
      white-space: nowrap;
      flex-shrink: 0;
    }
    .result-download-btn:hover {
      opacity: 0.9;
      transform: translateY(-1px);
    }

    @media (max-width: 768px) {
      .page-grid {
        grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
        gap: 10px;
      }
      .split-mode-btn {
        padding: 8px 12px;
        font-size: 0.78rem;
      }
      .result-item {
        flex-wrap: wrap;
      }
    }