/* --- Modern Tabs Bar --- */
  .tabs-wrapper {
    width: 100%;
    max-width: 780px;
    margin: 0 auto 32px auto;
    padding: 0 20px;
    box-sizing: border-box;
  }

  .tabs-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 6px;
    gap: 6px;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
  }
  .tabs-container::-webkit-scrollbar {
    display: none;
  }

  .tab-btn {
    flex: 1 1 auto;
    white-space: nowrap;
    background: transparent;
    border: 1px solid transparent;
    color: var(--text-muted);
    font-size: 0.9rem;
    font-weight: 600;
    padding: 10px 16px;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
    white-space: nowrap;
    text-align: center;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
  }

  .tab-btn:hover {
    color: var(--text-main);
    background: rgba(255, 255, 255, 0.04);
  }

  .tab-btn.active {
    background: var(--bg-surface);
    color: var(--accent);
    border-color: rgba(0, 210, 255, 0.35);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
  }

  /* --- Tool Workspace Container --- */
  .tool-wrapper {
    width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding-bottom: 60px;
  }

  .tab-content {
    display: none;
    width: 100%;
    max-width: 780px;
    margin: 0 auto;
    padding: 0 20px;
    box-sizing: border-box;
  }

  .tab-content.active {
    display: block;
  }

  .tool-container {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    padding: 36px 32px;
    box-sizing: border-box;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
  }

  .tool-container h3 {
    margin-top: 0;
    font-size: 1.4rem;
    color: var(--text-main);
    margin-bottom: 8px;
    letter-spacing: -0.02em;
    display: flex;
    align-items: center;
    gap: 10px;
  }

  .tool-desc {
    color: var(--text-muted);
    font-size: 0.92rem;
    margin-bottom: 24px;
    line-height: 1.5;
  }

  label {
    display: block;
    font-size: 0.88rem;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text-muted);
  }

  /* --- Modern Drag & Drop Upload Zone --- */
  .upload-box {
    background: var(--bg-base);
    border: 2px dashed rgba(0, 210, 255, 0.35);
    border-radius: 16px;
    padding: 36px 20px;
    text-align: center;
    cursor: pointer;
    transition: all 0.25s ease;
    margin-bottom: 20px;
  }

  .upload-box:hover, .upload-box.dragover {
    border-color: var(--accent);
    background: rgba(0, 210, 255, 0.04);
    transform: translateY(-2px);
  }

  .upload-icon {
    width: 48px;
    height: 48px;
    margin-bottom: 12px;
    color: var(--accent);
  }

  .upload-box-title {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 6px;
    color: var(--text-main);
  }

  .upload-box-sub {
    color: var(--text-subtle);
    font-size: 0.85rem;
    margin-bottom: 14px;
  }

  .upload-btn-pill {
    display: inline-block;
    background: var(--bg-surface);
    border: 1px solid var(--border-color);
    color: var(--text-main);
    padding: 8px 18px;
    border-radius: 8px;
    font-size: 0.88rem;
    font-weight: 600;
    pointer-events: none;
    transition: all 0.2s;
  }

  .upload-box:hover .upload-btn-pill {
    background: var(--accent);
    color: #08090d;
    border-color: var(--accent);
  }

  /* --- Active Single-File Card --- */
  .active-file-card {
    background: var(--bg-base);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 14px 18px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 14px;
    margin-bottom: 20px;
  }

  .active-file-info {
    display: flex;
    align-items: center;
    gap: 12px;
    min-width: 0;
  }

  .active-file-name {
    font-size: 0.95rem;
    font-weight: 700;
    color: var(--text-main);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  .active-file-meta {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-top: 2px;
  }

  .btn-remove-file {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: #f87171;
    padding: 6px 12px;
    border-radius: 6px;
    font-size: 0.82rem;
    font-weight: 600;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    flex-shrink: 0;
    transition: all 0.2s;
  }

  .btn-remove-file:hover {
    background: rgba(239, 68, 68, 0.2);
    border-color: #f87171;
  }

  /* --- Queue Header & Sortable List --- */
  .queue-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 12px;
    padding: 0 4px;
  }

  .queue-count {
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--accent);
  }

  .btn-clear-queue {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-muted);
    padding: 4px 10px;
    border-radius: 6px;
    font-size: 0.78rem;
    font-weight: 600;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: all 0.2s;
  }

  .btn-clear-queue:hover {
    background: rgba(239, 68, 68, 0.12);
    border-color: rgba(239, 68, 68, 0.4);
    color: #f87171;
  }

  ul.sortable-list {
    padding: 0;
    margin: 0 0 24px 0;
    list-style: none;
  }

  .sortable-item {
    background: var(--bg-base);
    border: 1px solid var(--border-color);
    padding: 12px 16px;
    margin-top: 8px;
    border-radius: 8px;
    color: var(--text-main);
    font-size: 0.92rem;
    display: flex;
    align-items: center;
    gap: 12px;
    box-sizing: border-box;
    transition: border-color 0.2s;
  }

  .sortable-item:hover {
    border-color: rgba(0, 210, 255, 0.3);
  }

  .item-name {
    flex: 1 1 auto;
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    font-weight: 500;
  }

  .item-actions {
    flex: 0 0 auto;
    display: flex;
    gap: 6px;
  }

  .icon-btn {
    width: 32px;
    height: 32px;
    flex: 0 0 auto;
    background: var(--bg-surface);
    color: var(--text-muted);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
  }

  .icon-btn:hover:not(:disabled) {
    background: var(--bg-surface);
    border-color: var(--accent);
    color: var(--accent);
  }

  .icon-btn-delete:hover:not(:disabled) {
    background: rgba(239, 68, 68, 0.15);
    border-color: rgba(239, 68, 68, 0.5);
    color: #f87171;
  }

  .icon-btn:disabled {
    opacity: 0.3;
    cursor: not-allowed;
  }

  /* Options Form Controls */
  input[type="text"], select {
    width: 100%;
    padding: 12px 16px;
    background-color: var(--bg-base);
    color: var(--text-main);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    box-sizing: border-box;
    margin-bottom: 20px;
    font-family: inherit;
    font-size: 0.95rem;
    transition: border-color 0.2s;
  }

  input[type="text"]:focus, select:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 1px rgba(0, 210, 255, 0.3);
  }

  .options-row {
    display: flex;
    gap: 16px;
    margin-bottom: 8px;
  }
  .options-col { flex: 1; min-width: 0; }

  /* --- Action Buttons (100% Emoji-Free) --- */
  .btn-accent {
    background: var(--accent);
    color: #08090d;
    border: none;
    padding: 14px 28px;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.2s ease;
    width: 100%;
    margin-top: 8px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
  }

  .btn-accent:hover {
    background: #33ddff;
    box-shadow: 0 4px 16px rgba(0, 210, 255, 0.35);
    transform: translateY(-1px);
  }

  .download-btn {
    display: none;
    background-color: var(--text-main);
    color: #08090d;
    text-align: center;
    text-decoration: none;
    padding: 14px 28px;
    border-radius: 10px;
    font-weight: 700;
    margin-top: 16px;
    transition: all 0.2s;
    align-items: center;
    justify-content: center;
    gap: 8px;
  }

  .download-btn:hover {
    background-color: var(--text-main);
    box-shadow: 0 4px 16px rgba(255, 255, 255, 0.2);
  }

  .status-text {
    text-align: center;
    margin-top: 14px;
    font-size: 0.92rem;
    font-weight: 600;
    color: var(--text-muted);
  }

  /* --- SEO & Educational Section --- */
  .seo-article {
    width: 100%;
    max-width: 780px;
    margin: 40px auto 20px auto;
    color: var(--text-muted);
    line-height: 1.7;
    font-size: 0.98rem;
    border-top: 1px solid var(--border-color);
    padding-top: 40px;
  }

  .seo-article h2, .seo-article h3 {
    color: var(--text-main);
    margin-top: 1.5rem;
    margin-bottom: 1rem;
  }

  .seo-article h2 { font-size: 1.4rem; font-weight: 800; }
  .seo-article h3 { font-size: 1.1rem; font-weight: 700; }
  .seo-article ul { padding-left: 20px; }
  .seo-article li { margin-bottom: 10px; }

  .faq-box { margin-bottom: 16px; }
  .faq-box details {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 18px 24px;
    cursor: pointer;
  }

  .faq-box summary {
    font-weight: 600;
    color: var(--text-main);
    outline: none;
    list-style: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
  }
  .faq-box summary::-webkit-details-marker { display: none; }

  .faq-box p {
    margin: 14px 0 0 0;
    font-size: 0.95rem;
    color: var(--text-muted);
    line-height: 1.65;
    font-weight: 400;
  }

  @media (max-width: 640px) {
    .clean-header h1 { font-size: 2rem; }
    .tool-container { padding: 24px 18px; }
    .options-row { flex-direction: column; gap: 8px; }}

  @media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
      animation-duration: 0.01ms !important;
      animation-iteration-count: 1 !important;
      transition-duration: 0.01ms !important;
      scroll-behavior: auto !important;
    }}