body {
    font-family: Georgia, 'Times New Roman', serif;
    font-size: 18px;
    line-height: 1.8;
    color: #1a1a1a;
    max-width: 780px;
    margin: 0 auto;
    padding: 2rem 1.5rem 5rem;
    background: #fff;
  }
  h1 { font-size: 2.1rem; line-height: 1.2; margin-bottom: 0.4rem; font-weight: 700; }
  h2 {
    font-size: 1.45rem;
    margin-top: 3rem;
    margin-bottom: 0.75rem;
    border-bottom: 2px solid #ececec;
    padding-bottom: 0.4rem;
    font-weight: 700;
  }
  h3 { font-size: 1.1rem; margin-top: 2rem; margin-bottom: 0.5rem; font-weight: 700; }
  p { margin: 0 0 1.25rem; }
  ul, ol { margin: 0 0 1.25rem 1.6rem; }
  li { margin-bottom: 0.5rem; }
  strong { font-weight: 700; }
  em { font-style: italic; }

  .byline { color: #555; font-size: 0.9rem; margin-bottom: 0.3rem; font-family: -apple-system, sans-serif; }
  .subtitle { font-size: 1.05rem; color: #444; font-style: italic; margin-bottom: 2rem; margin-top: 0.5rem; }

  .definition-block {
    background: #f5f5f5;
    border-left: 5px solid #111;
    padding: 1.25rem 1.6rem;
    margin: 2rem 0;
    border-radius: 0 6px 6px 0;
  }
  .definition-block p { margin: 0 0 0.5rem; }
  .definition-block p:last-child { margin: 0; }
  .definition-block .label {
    font-family: -apple-system, sans-serif;
    font-size: 0.78rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: #666;
    margin-bottom: 0.5rem;
    display: block;
  }

  .callout {
    background: #fffbf0;
    border-left: 5px solid #d4a012;
    padding: 1.1rem 1.5rem;
    margin: 2rem 0;
    border-radius: 0 6px 6px 0;
  }
  .callout p { margin: 0 0 0.5rem; }
  .callout p:last-child { margin: 0; }
  .callout.critical { background: #fff5f5; border-left-color: #c0392b; }

  .geolab-toc {
    background: #f8f8f8;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    padding: 1.1rem 1.4rem;
    margin: 1.75rem 0 2rem;
    font-family: -apple-system, sans-serif;
    font-size: 0.9rem;
  }
  .geolab-toc .toc-label {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.07em;
    color: #888;
    margin-bottom: 0.6rem;
    display: block;
  }
  .geolab-toc ol { margin: 0; padding-left: 1.3rem; }
  .geolab-toc li { margin-bottom: 0.3rem; }
  .geolab-toc a { color: #2E75B6; text-decoration: none; }
  .geolab-toc a:hover { text-decoration: underline; }

  /* Results table */
  .results-table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.25rem 0 0.5rem;
    font-family: -apple-system, sans-serif;
    font-size: 0.91rem;
  }
  .results-table th {
    padding: 0.65rem 1rem;
    text-align: left;
    font-weight: 700;
    font-size: 0.82rem;
    background: #111;
    color: #fff;
  }
  .results-table th:first-child { border-radius: 6px 0 0 0; }
  .results-table th:last-child  { border-radius: 0 6px 0 0; }
  .results-table td {
    padding: 0.65rem 1rem;
    border-bottom: 1px solid #efefef;
    vertical-align: middle;
  }
  .results-table td:first-child { font-weight: 700; }
  .results-table tr:nth-child(even) td { background: #fafafa; }
  .results-table tr.total-row td { background: #f0f0f0; font-weight: 700; border-bottom: none; }
  .results-table tr:last-child td:first-child { border-radius: 0 0 0 6px; }
  .results-table tr:last-child td:last-child  { border-radius: 0 0 6px 0; }
  .results-caption {
    font-family: -apple-system, sans-serif;
    font-size: 0.8rem;
    color: #888;
    margin-top: 0.4rem;
    margin-bottom: 1.75rem;
  }

  /* Platform blocks */
  .platform-block {
    border-left: 4px solid #e0e0e0;
    padding: 0.75rem 1.25rem;
    margin: 1.25rem 0;
  }
  .platform-block.perplexity { border-color: #20b2aa; }
  .platform-block.chatgpt    { border-color: #74aa9c; }
  .platform-block.aio        { border-color: #4285f4; }
  .platform-name {
    font-family: -apple-system, sans-serif;
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.07em;
    margin-bottom: 0.4rem;
    display: block;
  }
  .platform-block.perplexity .platform-name { color: #20b2aa; }
  .platform-block.chatgpt    .platform-name { color: #74aa9c; }
  .platform-block.aio        .platform-name { color: #4285f4; }
  .platform-block p { margin: 0; font-size: 0.97rem; }

  /* Method grid */
  .method-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin: 1.25rem 0 1.75rem;
  }
  .method-card {
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    padding: 1rem 1.1rem;
  }
  .method-card .mc-label {
    font-family: -apple-system, sans-serif;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.07em;
    color: #888;
    margin-bottom: 0.4rem;
    display: block;
  }
  .method-card p {
    font-family: -apple-system, sans-serif;
    font-size: 0.9rem;
    margin: 0;
    color: #333;
    line-height: 1.55;
  }

  /* Tier comparison */
  .tier-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin: 1.5rem 0 2rem;
  }
  .tier-card {
    border-radius: 8px;
    padding: 1.1rem 1.25rem;
    font-family: -apple-system, sans-serif;
    font-size: 0.91rem;
  }
  .tier-card.t1 { background: #f0f4ff; border-left: 4px solid #2E75B6; }
  .tier-card.t2 { background: #f5f5f5; border-left: 4px solid #888; }
  .tier-card .tier-label {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.07em;
    margin-bottom: 0.5rem;
    display: block;
  }
  .tier-card.t1 .tier-label { color: #2E75B6; }
  .tier-card.t2 .tier-label { color: #888; }
  .tier-card .tier-rate {
    font-size: 2rem;
    font-weight: 800;
    font-family: -apple-system, sans-serif;
    display: block;
    margin-bottom: 0.3rem;
  }
  .tier-card.t1 .tier-rate { color: #2E75B6; }
  .tier-card.t2 .tier-rate { color: #888; }
  .tier-card p { margin: 0; font-size: 0.88rem; color: #555; line-height: 1.5; }

  /* Noise floor summary */
  .noise-floor-block {
    background: #111;
    color: #fff;
    border-radius: 8px;
    padding: 1.5rem 1.75rem;
    margin: 2rem 0;
    font-family: -apple-system, sans-serif;
  }
  .noise-floor-block .nf-label {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: #888;
    margin-bottom: 1rem;
    display: block;
  }
  .noise-floor-block .nf-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.25rem;
  }
  .noise-floor-block .nf-item .nf-value {
    font-size: 1.6rem;
    font-weight: 800;
    color: #d4a012;
    display: block;
    line-height: 1.1;
    margin-bottom: 0.2rem;
  }
  .noise-floor-block .nf-item .nf-desc {
    font-size: 0.82rem;
    color: #aaa;
    line-height: 1.4;
  }

  code {
    font-family: 'Courier New', Courier, monospace;
    font-size: 0.88em;
    background: #f0f0f0;
    padding: 0.15em 0.4em;
    border-radius: 3px;
    color: #c0392b;
  }

  .faq-item { margin-bottom: 1.75rem; }
  .faq-item h3 { margin-bottom: 0.5rem; font-size: 1.05rem; }

  .review-card {
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    padding: 1.25rem 1.5rem;
    margin: 1.25rem 0;
    font-family: -apple-system, sans-serif;
    background: #fafafa;
  }
  .review-card blockquote {
    margin: 0 0 0.75rem;
    font-style: italic;
    color: #333;
    font-size: 0.95rem;
    line-height: 1.6;
    border: none;
    padding: 0;
  }
  .reviewer-meta { font-size: 0.85rem; color: #555; }
  .reviewer-meta strong { color: #111; }
  .rating-stars { color: #d4a012; font-size: 0.9rem; margin-top: 0.2rem; }

  .meta-section {
    font-family: -apple-system, sans-serif;
    font-size: 0.88rem;
    color: #555;
    border-top: 1px solid #e0e0e0;
    padding-top: 1.5rem;
    margin-top: 3rem;
  }
  .meta-section h2 {
    font-size: 1rem;
    font-family: -apple-system, sans-serif;
    border: none;
    margin-top: 1.5rem;
    padding: 0;
    color: #333;
  }
  .meta-section ul { margin-left: 1.2rem; }
  .meta-section li { margin-bottom: 0.3rem; }

  .author-bio {
    background: #f8f8f8;
    border-radius: 8px;
    padding: 1.25rem 1.5rem;
    margin-top: 2.5rem;
    font-family: -apple-system, sans-serif;
    font-size: 0.9rem;
    color: #444;
  }
  .author-bio strong { color: #111; }

  pre {
    background: #1a1a1a;
    color: #f0f0f0;
    padding: 1.1rem 1.2rem;
    border-radius: 6px;
    font-size: 0.82rem;
    line-height: 1.7;
    overflow-x: auto;
    font-family: 'Courier New', Courier, monospace;
  }

  @media (max-width: 560px) {
    .method-grid, .tier-grid, .noise-floor-block .nf-grid { grid-template-columns: 1fr; }
    body { font-size: 17px; }
    h1 { font-size: 1.7rem; }
  }