/* Export page layout */
    .export-shell {
      display: grid;
      grid-template-columns: minmax(0, 1fr) 380px;
      gap: 36px;
      align-items: start;
      padding: 38px 56px 88px;
      max-width: 1440px;
      margin: 0 auto;
    }
    @media (max-width: 1280px) {
      .export-shell { grid-template-columns: minmax(0, 1fr) 380px; gap: 36px; }
    }
    @media (max-width: 1100px) {
      .export-shell { grid-template-columns: 1fr; }
    }

    /* Section blocks */
    .section-block {
      background: var(--surface);
      border: 1px solid rgba(20,23,31,.08);
      border-radius: var(--r-lg);
      padding: 24px;
      margin-bottom: 20px;
      box-shadow: 0 14px 38px rgba(20,23,31,.055);
    }
    .section-block h3 {
      font-family: var(--font-serif);
      font-size: 15px;
      font-weight: 600;
      margin-bottom: 4px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .section-block .section-sub {
      font-size: 12px;
      color: var(--muted);
      margin-bottom: 16px;
    }
    .section-step {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      width: 22px; height: 22px;
      background: var(--ink);
      color: #fff;
      border-radius: 50%;
      font-size: 11px;
      font-family: var(--font-mono);
      font-weight: 600;
    }

    /* Format card grid */
    .format-grid {
      display: grid;
      grid-template-columns: repeat(5, 1fr);
      gap: 10px;
    }
    @media (max-width: 1400px) { .format-grid { grid-template-columns: repeat(4, 1fr); } }
    @media (max-width: 1100px) { .format-grid { grid-template-columns: repeat(3, 1fr); } }
    @media (max-width: 700px)  { .format-grid { grid-template-columns: repeat(2, 1fr); } }

    .format-card {
      background: var(--surface);
      border: 1.5px solid var(--border);
      border-radius: 10px;
      padding: 14px 12px;
      cursor: pointer;
      transition: all .18s;
      position: relative;
      text-align: left;
    }
    .format-card:hover {
      border-color: var(--ink);
      transform: translateY(-1px);
    }
    .format-card.disabled {
      cursor: not-allowed;
      opacity: .58;
      background: var(--surface-2);
    }
    .format-card.disabled:hover {
      border-color: var(--border);
      transform: none;
    }
    .format-card.selected {
      border-color: var(--accent);
      background: linear-gradient(180deg, rgba(31,63,217,.04), var(--surface));
      box-shadow: 0 0 0 3px rgba(31,63,217,.10);
    }
    .format-check {
      position: absolute;
      top: 10px;
      right: 10px;
      width: 16px;
      height: 16px;
      border-radius: 50%;
      border: 1.5px solid var(--border);
      display: flex;
      align-items: center;
      justify-content: center;
      color: #fff;
      transition: all .15s;
    }
    .format-card.selected .format-check {
      background: var(--accent);
      border-color: var(--accent);
    }
    .format-icon {
      width: 32px;
      height: 32px;
      border-radius: 7px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-family: var(--font-mono);
      font-size: 10px;
      font-weight: 700;
      color: #fff;
      letter-spacing: -.02em;
      margin-bottom: 10px;
    }
    .format-name {
      font-size: 13px;
      font-weight: 600;
      color: var(--ink);
      margin-bottom: 2px;
    }
    .format-ext {
      font-family: var(--font-mono);
      font-size: 10px;
      color: var(--muted);
      margin-bottom: 6px;
    }
    .format-desc {
      font-size: 11px;
      color: var(--muted);
      line-height: 1.4;
    }

    /* Content options */
    .options-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 10px;
    }
    @media (max-width: 700px) { .options-grid { grid-template-columns: 1fr; } }

    .option-card {
      display: flex;
      gap: 12px;
      padding: 14px;
      border: 1px solid var(--border);
      border-radius: 10px;
      cursor: pointer;
      transition: all .15s;
      align-items: flex-start;
    }
    .option-card:hover { border-color: var(--ink); }
    .option-card.checked {
      border-color: var(--accent);
      background: rgba(31,63,217,.03);
    }
    .option-check {
      width: 18px;
      height: 18px;
      border-radius: 5px;
      border: 1.5px solid var(--border);
      flex-shrink: 0;
      display: flex;
      align-items: center;
      justify-content: center;
      color: #fff;
      margin-top: 1px;
    }
    .option-card.checked .option-check {
      background: var(--accent);
      border-color: var(--accent);
    }
    .option-content { flex: 1; }
    .option-title {
      font-size: 13px;
      font-weight: 600;
      color: var(--ink);
      margin-bottom: 3px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .option-desc {
      font-size: 11px;
      color: var(--muted);
      line-height: 1.5;
    }
    .option-meta {
      font-family: var(--font-mono);
      font-size: 10px;
      color: var(--muted);
      padding: 1px 6px;
      border: 1px solid var(--border);
      border-radius: 3px;
    }

    /* Actions row */
    .actions-row {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 10px;
      margin-top: 16px;
    }
    @media (max-width: 900px) { .actions-row { grid-template-columns: repeat(2, 1fr); } }

    .history-overlay {
      position: fixed;
      inset: 0;
      background: rgba(20, 23, 31, .28);
      display: flex;
      align-items: center;
      justify-content: center;
      z-index: 120;
      padding: 24px;
    }
    .history-panel {
      width: min(560px, 100%);
      max-height: 70vh;
      overflow: auto;
      background: var(--surface);
      border: 1px solid var(--border);
      border-radius: var(--r-lg);
      box-shadow: var(--shadow-lg);
      padding: 18px;
    }
    .history-head {
      display: flex;
      align-items: center;
      justify-content: space-between;
      margin-bottom: 12px;
    }
    .history-head h3 {
      font-family: var(--font-serif);
      font-size: 17px;
    }
    .history-item {
      display: grid;
      grid-template-columns: 1fr auto;
      gap: 8px;
      padding: 12px 0;
      border-top: 1px solid var(--border);
    }
    .history-source {
      font-weight: 600;
      color: var(--ink);
    }
    .history-meta {
      font-size: 12px;
      color: var(--muted);
      margin-top: 2px;
    }
    .history-formats {
      font-family: var(--font-mono);
      font-size: 11px;
      color: var(--accent);
      text-align: right;
    }

    .action-tile {
      background: var(--surface);
      border: 1px solid var(--border);
      border-radius: 10px;
      padding: 14px;
      cursor: pointer;
      transition: all .15s;
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .action-tile:hover {
      border-color: var(--ink);
      transform: translateY(-1px);
    }
    .action-icon {
      width: 36px; height: 36px;
      border-radius: 8px;
      background: var(--bg);
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--accent);
      flex-shrink: 0;
    }
    .action-text {
      flex: 1;
      min-width: 0;
    }
    .action-text .t {
      font-size: 12px;
      font-weight: 600;
      color: var(--ink);
      margin-bottom: 1px;
    }
    .action-text .s {
      font-size: 10px;
      color: var(--muted);
      white-space: nowrap;
      overflow: hidden;
      text-overflow: ellipsis;
    }

    /* Preview panel — spec book */
    .spec-book {
      position: sticky;
      top: calc(var(--header-h) + var(--project-status-h) + 24px);
    }
    .spec-cover {
      background: linear-gradient(135deg, #14171F 0%, #1F3FD9 100%);
      border-radius: 12px;
      padding: 28px 22px;
      color: #fff;
      position: relative;
      aspect-ratio: 4 / 5;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      overflow: hidden;
      margin-bottom: 14px;
      box-shadow: 0 14px 30px -10px rgba(20,23,31,.35);
    }
    .spec-cover::before {
      content: '';
      position: absolute;
      inset: 0;
      background: radial-gradient(circle at 70% 20%, rgba(255,255,255,.12), transparent 50%);
      pointer-events: none;
    }
    .spec-cover-top { position: relative; z-index: 1; }
    .spec-cover-label {
      font-family: var(--font-mono);
      font-size: 10px;
      letter-spacing: .14em;
      text-transform: uppercase;
      opacity: .65;
      margin-bottom: 12px;
    }
    .spec-cover-title {
      font-family: var(--font-serif);
      font-size: 26px;
      font-weight: 600;
      line-height: 1.15;
      margin-bottom: 8px;
    }
    .spec-cover-sub {
      font-family: var(--font-display);
      font-size: 14px;
      font-style: italic;
      opacity: .8;
    }
    .spec-cover-palette {
      display: flex;
      gap: 4px;
      position: relative;
      z-index: 1;
    }
    .spec-cover-palette > div {
      flex: 1;
      height: 36px;
      border-radius: 3px;
    }
    .spec-cover-meta {
      position: relative; z-index: 1;
      display: flex;
      justify-content: space-between;
      font-family: var(--font-mono);
      font-size: 10px;
      opacity: .7;
      letter-spacing: .04em;
    }

    /* Thumbnails */
    .spec-thumbs {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 6px;
      margin-bottom: 14px;
    }
    .spec-thumb {
      background: var(--surface);
      border: 1px solid var(--border);
      border-radius: 6px;
      aspect-ratio: 1;
      padding: 6px;
      position: relative;
      overflow: hidden;
      cursor: pointer;
    }
    .spec-thumb:hover { border-color: var(--accent); }
    .spec-thumb-label {
      position: absolute;
      bottom: 3px; left: 4px;
      font-family: var(--font-mono);
      font-size: 8px;
      color: var(--muted);
      letter-spacing: .04em;
    }
    .spec-thumb-bars {
      display: flex;
      gap: 1px;
      height: 100%;
      align-items: flex-end;
    }
    .spec-thumb-bars > div { flex: 1; border-radius: 1px; }

    .file-info {
      background: var(--bg);
      border-radius: 8px;
      padding: 12px 14px;
      margin-bottom: 14px;
    }
    .file-info-row {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 4px 0;
      font-size: 11px;
    }
    .file-info-row .k { color: var(--muted); }
    .file-info-row .v {
      font-family: var(--font-mono);
      color: var(--ink);
      font-weight: 500;
    }

    /* Big export button */
    .export-btn-big {
      width: 100%;
      padding: 14px;
      font-size: 14px;
      background: var(--ink);
      color: #fff;
      border: none;
      border-radius: 10px;
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      transition: all .15s;
      font-family: var(--font-sans);
      font-weight: 500;
    }
    .export-btn-big:hover { background: var(--accent); transform: translateY(-1px); }

    /* Summary banner */
    .summary-banner {
      display: flex;
      align-items: center;
      gap: 16px;
      padding: 14px 18px;
      background: linear-gradient(90deg, var(--ink), #2A2F40);
      border-radius: var(--r-lg);
      color: #fff;
      margin-bottom: 16px;
    }
    .summary-palette {
      display: flex;
      gap: 3px;
      flex-shrink: 0;
    }
    .summary-palette > div {
      width: 18px; height: 28px;
      border-radius: 3px;
    }
    .summary-text { flex: 1; }
    .summary-text .t {
      font-family: var(--font-serif);
      font-size: 14px;
      font-weight: 600;
      margin-bottom: 2px;
    }
    .summary-text .s {
      font-size: 11px;
      opacity: .7;
      font-family: var(--font-mono);
    }
    .summary-stat {
      text-align: right;
    }
    .summary-stat .num {
      font-family: var(--font-display);
      font-size: 22px;
      font-weight: 500;
    }
    .summary-stat .label {
      font-size: 10px;
      opacity: .7;
      text-transform: uppercase;
      letter-spacing: .08em;
    }