.centerpiece-wrapper {
      margin-top: 1.5rem;
      background: linear-gradient(180deg, rgba(18, 24, 38, 0.95) 0%, rgba(12, 16, 26, 0.98) 100%);
      border: 1px solid var(--border-highlight);
      border-radius: var(--radius-lg);
      padding: clamp(1.2rem, 3vw, 2rem);
      box-shadow: 0 10px 35px var(--seo-glow);
    }
    .attribute-pills {
      display: flex;
      flex-wrap: wrap;
      gap: 0.6rem;
      margin-bottom: 1.2rem;
    }
    .attr-pill {
      display: inline-flex;
      align-items: center;
      gap: 0.4rem;
      padding: 0.35rem 0.75rem;
      border-radius: 9999px;
      font-size: 0.82rem;
      font-weight: 600;
      background: rgba(16, 185, 129, 0.12);
      color: var(--seo-emerald);
      border: 1px solid rgba(16, 185, 129, 0.25);
    }
    .attr-pill.cyan {
      background: rgba(6, 182, 212, 0.12);
      color: var(--seo-cyan);
      border-color: rgba(6, 182, 212, 0.25);
    }
    .attr-pill.violet {
      background: rgba(139, 92, 246, 0.12);
      color: var(--ai-violet);
      border-color: rgba(139, 92, 246, 0.25);
    }
    
    /* Centerpiece Layout */
    .centerpiece-grid {
      display: grid;
      grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
      gap: 2rem;
      align-items: start;
    }
    .centerpiece-intro h1 {
      font-size: clamp(1.8rem, 3.5vw, 2.75rem);
      font-weight: 750;
      line-height: 1.15;
      letter-spacing: -0.035em;
      margin-bottom: 0.75rem;
      color: #ffffff;
    }
    .centerpiece-intro .author-kicker {
      display: inline-block;
      font-family: var(--font-mono);
      font-size: 0.85rem;
      color: var(--seo-emerald);
      text-transform: uppercase;
      letter-spacing: 0.08em;
      margin-bottom: 0.5rem;
      font-weight: 600;
    }
    .centerpiece-intro .triad-summary {
      font-size: 1.05rem;
      color: var(--text-secondary);
      margin-bottom: 1.5rem;
      line-height: 1.6;
    }
    .centerpiece-ctas {
      display: flex;
      flex-wrap: wrap;
      gap: 0.85rem;
    }
    .btn-primary {
      display: inline-flex;
      align-items: center;
      gap: 0.5rem;
      padding: 0.8rem 1.4rem;
      border-radius: var(--radius-sm);
      background: linear-gradient(135deg, var(--seo-emerald), #059669);
      color: #ffffff !important;
      font-weight: 650;
      font-size: 0.95rem;
      box-shadow: 0 4px 15px rgba(16, 185, 129, 0.35);
      border: 1px solid #10b981;
      cursor: pointer;
      text-decoration: none;
      transition: transform 0.2s ease, box-shadow 0.2s ease;
    }
    .btn-primary:hover {
      transform: translateY(-2px);
      box-shadow: 0 6px 20px rgba(16, 185, 129, 0.5);
    }
    .btn-secondary {
      display: inline-flex;
      align-items: center;
      gap: 0.5rem;
      padding: 0.8rem 1.4rem;
      border-radius: var(--radius-sm);
      background: rgba(255, 255, 255, 0.05);
      color: #ffffff !important;
      font-weight: 600;
      font-size: 0.95rem;
      border: 1px solid var(--border-card);
      cursor: pointer;
      text-decoration: none;
      transition: background 0.2s ease, border-color 0.2s ease;
    }
    .btn-secondary:hover {
      background: rgba(255, 255, 255, 0.1);
      border-color: rgba(255, 255, 255, 0.3);
    }
    
    /* Interactive Chapter Viewer inside Centerpiece */
    .chapter-interactive-box {
      background: var(--bg-surface);
      border: 1px solid var(--border-card);
      border-radius: var(--radius-md);
      padding: 1.25rem;
    }
    .chapter-box-header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      margin-bottom: 1rem;
      border-bottom: 1px solid var(--border-subtle);
      padding-bottom: 0.75rem;
    }
    .chapter-box-header h3 {
      font-size: 1rem;
      font-weight: 650;
      color: var(--text-primary);
    }
    .chapter-badge {
      font-size: 0.75rem;
      font-family: var(--font-mono);
      background: rgba(6, 182, 212, 0.15);
      color: var(--seo-cyan);
      padding: 0.2rem 0.5rem;
      border-radius: 4px;
    }
    .chapter-tabs {
      display: flex;
      gap: 0.4rem;
      margin-bottom: 1rem;
      overflow-x: auto;
      padding-bottom: 0.25rem;
    }
    .tab-btn {
      background: transparent;
      border: 1px solid var(--border-subtle);
      color: var(--text-secondary);
      padding: 0.35rem 0.65rem;
      border-radius: 4px;
      font-size: 0.78rem;
      font-weight: 600;
      cursor: pointer;
      white-space: nowrap;
      transition: all 0.2s ease;
    }
    .tab-btn.active, .tab-btn:hover {
      background: var(--bg-card);
      color: var(--seo-emerald);
      border-color: var(--seo-emerald);
    }
    .chapter-content-panel {
      min-height: 180px;
      font-size: 0.88rem;
      color: var(--text-secondary);
      line-height: 1.55;
    }
    .chapter-content-panel h4 {
      color: #ffffff;
      font-size: 0.95rem;
      margin-bottom: 0.4rem;
    }
    .chapter-content-panel p {
      margin-bottom: 0.75rem;
    }
    .chapter-content-panel ul {
      padding-left: 1.2rem;
      margin-bottom: 0.8rem;
    }
    .chapter-content-panel li { margin-bottom: 0.3rem; }
    
    /* 16:9 Visual Showcase Section */
    .hero-visual-section {
      padding-block: 3.5rem 2rem;
    }
    .visual-16-9-card {
      position: relative;
      width: 100%;
      aspect-ratio: 16 / 9;
      background: linear-gradient(135deg, #0d1527 0%, #06090e 100%);
      border: 1px solid var(--border-card);
      border-radius: var(--radius-lg);
      overflow: hidden;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
    }
    .visual-inner-canvas {
      width: 90%;
      height: 85%;
      display: grid;
      grid-template-columns: 1fr 1.2fr;
      align-items: center;
      gap: 2.5rem;
    }
    .book-3d-presentation {
      display: flex;
      justify-content: center;
    }
    .book-spine-cover {
      width: 220px;
      height: 310px;
      background: linear-gradient(145deg, #111a2e 0%, #0a0f1d 100%);
      border: 1px solid rgba(16, 185, 129, 0.4);
      border-radius: 4px 14px 14px 4px;
      box-shadow: -10px 10px 30px rgba(0,0,0,0.8), inset 4px 0 8px rgba(255,255,255,0.1);
      padding: 1.5rem 1.2rem;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      position: relative;
    }
    .book-cover-title {
      font-size: 1.15rem;
      font-weight: 800;
      line-height: 1.2;
      color: #ffffff;
      border-bottom: 2px solid var(--seo-emerald);
      padding-bottom: 0.6rem;
    }
    .book-cover-subtitle {
      font-size: 0.72rem;
      color: var(--text-secondary);
      margin-top: 0.5rem;
    }
    .book-cover-author {
      font-size: 0.85rem;
      font-weight: 700;
      color: var(--seo-emerald);
      margin-top: auto;
    }
    .book-cover-meta {
      font-size: 0.65rem;
      color: var(--text-muted);
      font-family: var(--font-mono);
      display: flex;
      justify-content: space-between;
      border-top: 1px solid var(--border-subtle);
      padding-top: 0.4rem;
    }
    .visual-text-details h2 {
      font-size: clamp(1.4rem, 2.5vw, 2.1rem);
      font-weight: 700;
      margin-bottom: 0.75rem;
      letter-spacing: -0.02em;
    }
    .visual-text-details p {
      color: var(--text-secondary);
      font-size: 0.95rem;
      line-height: 1.6;
      margin-bottom: 1.2rem;
    }
    .bibliographic-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 0.6rem;
      font-size: 0.82rem;
    }
    .biblio-item {
      background: rgba(255, 255, 255, 0.03);
      padding: 0.4rem 0.75rem;
      border-radius: var(--radius-sm);
      border: 1px solid var(--border-subtle);
    }
    .biblio-label { color: var(--text-muted); font-size: 0.75rem; }
    .biblio-val { color: var(--text-primary); font-weight: 600; }
    
    /* Comprehensive SVG Infographic Section */
    .infographic-section {
      padding-block: 3.5rem;
    }
    .infographic-container {
      background: var(--bg-surface);
      border: 1px solid var(--border-card);
      border-radius: var(--radius-lg);
      padding: clamp(1.5rem, 3.5vw, 2.5rem);
    }
    .infographic-header {
      margin-bottom: 1.5rem;
      text-align: center;
    }
    .infographic-header h2 {
      font-size: clamp(1.5rem, 2.8vw, 2.2rem);
      font-weight: 700;
      margin-bottom: 0.5rem;
    }
    .infographic-header p {
      color: var(--text-secondary);
      max-width: 48rem;
      margin-inline: auto;
      font-size: 0.95rem;
    }
    .vector-svg-wrapper {
      width: 100%;
      overflow-x: auto;
      margin-block: 1rem;
    }
    .vector-svg-wrapper svg {
      display: block;
      width: 100%;
      height: auto;
      min-width: 820px;
    }
    
    /* 2 Smaller Animated Spot Cards */
    .spot-cards-section {
      padding-block: 2.5rem;
    }
    .spot-cards-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
      gap: 1.5rem;
    }
    .spot-card {
      background: var(--bg-surface);
      border: 1px solid var(--border-card);
      border-radius: var(--radius-md);
      padding: 1.8rem;
      transition: transform 0.35s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.35s ease, border-color 0.35s ease;
      position: relative;
      overflow: hidden;
    }
    .spot-card::before {
      content: "";
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      height: 3px;
      background: linear-gradient(90deg, var(--seo-emerald), var(--seo-cyan));
    }
    .spot-card.violet::before {
      background: linear-gradient(90deg, var(--ai-violet), var(--seo-cyan));
    }
    .spot-card:hover {
      transform: translateY(-4px) scale(1.015);
      box-shadow: 0 16px 36px rgba(0, 0, 0, 0.4), 0 0 24px rgba(16, 185, 129, 0.15);
      border-color: rgba(16, 185, 129, 0.4);
    }
    .spot-card.violet:hover {
      box-shadow: 0 16px 36px rgba(0, 0, 0, 0.4), 0 0 24px rgba(139, 92, 246, 0.18);
      border-color: rgba(139, 92, 246, 0.4);
    }
    .spot-badge {
      display: inline-block;
      font-family: var(--font-mono);
      font-size: 0.75rem;
      padding: 0.2rem 0.5rem;
      border-radius: 4px;
      background: rgba(16, 185, 129, 0.15);
      color: var(--seo-emerald);
      margin-bottom: 0.8rem;
      font-weight: 600;
    }
    .spot-card.violet .spot-badge {
      background: rgba(139, 92, 246, 0.15);
      color: var(--ai-violet);
    }
    .spot-card h3 {
      font-size: 1.25rem;
      font-weight: 700;
      margin-bottom: 0.6rem;
      color: #ffffff;
    }
    .spot-card p {
      font-size: 0.92rem;
      color: var(--text-secondary);
      line-height: 1.6;
      margin-bottom: 1rem;
    }
    .spot-diagram {
      background: var(--bg-card);
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-sm);
      padding: 1rem;
      font-family: var(--font-mono);
      font-size: 0.8rem;
      color: var(--text-secondary);
      margin-bottom: 0.8rem;
    }
    .spot-diagram .token-line {
      display: flex;
      justify-content: space-between;
      margin-bottom: 0.35rem;
      padding-bottom: 0.35rem;
      border-bottom: 1px dashed rgba(255, 255, 255, 0.08);
    }
    .spot-diagram .token-line:last-child { border-bottom: none; margin-bottom: 0; }
    .highlight-green { color: var(--seo-emerald); font-weight: 600; }
    .highlight-cyan { color: var(--seo-cyan); font-weight: 600; }
    .highlight-violet { color: var(--ai-violet); font-weight: 600; }

    /* Sample Chapter Modal / Output */
    .sample-reader-box {
      margin-block: 3rem;
      background: var(--bg-surface);
      border: 1px solid var(--border-card);
      border-radius: var(--radius-lg);
      padding: clamp(1.5rem, 3.5vw, 2.5rem);
    }
    .sample-reader-box details {
      width: 100%;
    }
    .sample-reader-box summary {
      cursor: pointer;
      list-style: none;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-size: 1.2rem;
      font-weight: 700;
      color: var(--text-primary);
      padding: 0.5rem 0;
    }
    .sample-reader-box summary::-webkit-details-marker { display: none; }
    .sample-reader-box summary span.action-hint {
      font-size: 0.85rem;
      font-family: var(--font-mono);
      color: var(--seo-cyan);
      border: 1px solid rgba(6, 182, 212, 0.3);
      padding: 0.35rem 0.75rem;
      border-radius: var(--radius-sm);
    }
    .sample-content {
      margin-top: 1.5rem;
      padding-top: 1.5rem;
      border-top: 1px solid var(--border-subtle);
      font-size: 0.98rem;
      line-height: 1.7;
      color: #cbd5e1;
    }
    .sample-content h4 {
      color: #ffffff;
      font-size: 1.3rem;
      margin-block: 1.2rem 0.5rem;
    }
    .sample-content p { margin-bottom: 1.1rem; }
    .sample-content blockquote {
      border-left: 3px solid var(--seo-emerald);
      padding-left: 1.2rem;
      margin-block: 1rem;
      font-style: italic;
      color: var(--text-secondary);
    }
    
    

@media (max-width: 900px) {
      .centerpiece-grid { grid-template-columns: 1fr; }
      .visual-16-9-card { aspect-ratio: auto; min-height: 520px; padding: 2rem; }
      .visual-inner-canvas { grid-template-columns: 1fr; width: 100%; height: auto; gap: 1.5rem; }
      .book-3d-presentation { display: none; }
      
    }