*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
  :root {
    --bg: #ffffff;
    --panel: #f7f8fa;
    --border: #e4e7ec;
    --text: #111418;
    --text-soft: #3a4149;
    --dim: #6b7380;
    --brand: #00668f;
    --brand-dark: #002855;
    --brand-soft: #e8f1f6;
  }
  html, body { background: var(--bg); color: var(--text); font-family: Arial, "Helvetica Neue", Helvetica, sans-serif; font-size: 17px; line-height: 1.65; }
  a { color: var(--brand); text-decoration: none; }
  a:hover { color: var(--brand-dark); text-decoration: underline; }

  /* Top nav — with pure-CSS mobile hamburger */
  .site-nav { background: #fff; border-bottom: 1px solid var(--border); position: sticky; top: 0; z-index: 20; }
  .site-nav-inner { max-width: 1120px; margin: 0 auto; padding: 1rem 1.5rem; display: flex; align-items: center; justify-content: space-between; gap: 1.5rem; position: relative; }
  .site-nav-brand { color: var(--brand-dark); text-decoration: none; font-weight: 700; font-size: 1.02rem; letter-spacing: 0.01em; white-space: nowrap; }
  .site-nav-brand:hover { color: var(--brand); text-decoration: none; }
  .site-nav-brand em { font-style: normal; color: var(--brand); font-weight: 700; }
  .site-nav-links { display: flex; gap: 1.6rem; align-items: center; flex-wrap: wrap; font-size: 0.92rem; }
  .site-nav-links a { color: var(--text-soft); text-decoration: none; font-weight: 500; transition: color 0.15s; }
  .site-nav-links a:hover { color: var(--brand); text-decoration: none; }
  .site-nav-cta { display: inline-block; padding: 0.55rem 1.1rem; background: var(--brand); color: #ffffff !important; border-radius: 3px; font-weight: 600; font-size: 0.88rem; letter-spacing: 0.01em; transition: background 0.15s; }
  .site-nav-cta:hover { background: var(--brand-dark); color: #ffffff !important; text-decoration: none; }
  .nav-toggle { display: none; }
  .nav-hamburger { display: none; width: 28px; height: 22px; cursor: pointer; flex-direction: column; justify-content: space-between; }
  .nav-hamburger span { display: block; height: 3px; background: var(--brand-dark); border-radius: 2px; transition: transform 0.2s, opacity 0.2s; }
  @media (max-width: 900px) {
    .nav-hamburger { display: flex; }
    .site-nav-links { display: none; position: absolute; top: 100%; left: 0; right: 0; background: #fff; flex-direction: column; align-items: stretch; gap: 0; padding: 0.5rem 0; border-bottom: 1px solid var(--border); box-shadow: 0 8px 24px rgba(0,0,0,0.08); }
    .site-nav-links a { padding: 0.85rem 1.5rem; border-bottom: 1px solid var(--border); width: 100%; }
    .site-nav-links a:last-child { border-bottom: none; }
    .site-nav-cta { margin: 0.75rem 1.5rem; text-align: center; }
    .nav-toggle:checked ~ .site-nav-links { display: flex; }
    .nav-toggle:checked ~ .nav-hamburger span:nth-child(1) { transform: translateY(9px) rotate(45deg); }
    .nav-toggle:checked ~ .nav-hamburger span:nth-child(2) { opacity: 0; }
    .nav-toggle:checked ~ .nav-hamburger span:nth-child(3) { transform: translateY(-10px) rotate(-45deg); }
    .site-nav-inner { padding: 0.85rem 1rem; }
  }

  /* Footer */
  .site-footer { background: var(--brand-dark); color: #c9d4dc; padding: 3.25rem 1.5rem 2rem; margin-top: 4rem; }
  .site-footer a { color: #c9d4dc; text-decoration: none; }
  .site-footer a:hover { color: #ffffff; }
  .site-footer-inner { max-width: 1120px; margin: 0 auto; display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 2.75rem; font-size: 0.92rem; }
  .site-footer h4 { font-size: 0.78rem; text-transform: uppercase; letter-spacing: 0.08em; color: #ffffff; margin-bottom: 1rem; font-weight: 700; }
  .site-footer ul { list-style: none; margin: 0; padding: 0; }
  .site-footer li { margin-bottom: 0.55rem; }
  .site-footer-brand p { font-size: 0.9rem; color: #c9d4dc; margin-bottom: 0.7rem; line-height: 1.55; }
  .site-footer-brand strong { color: #ffffff; display: block; margin-bottom: 0.55rem; font-size: 1rem; font-weight: 700; }
  .site-footer-bottom { max-width: 1120px; margin: 2.75rem auto 0; padding-top: 1.65rem; border-top: 1px solid rgba(255,255,255,0.1); font-size: 0.8rem; color: rgba(255,255,255,0.55); display: flex; justify-content: space-between; flex-wrap: wrap; gap: 1rem; }
  @media (max-width: 720px) {
    .site-footer-inner { grid-template-columns: 1fr 1fr; gap: 2rem; }
    .site-footer-brand { grid-column: 1 / -1; }
  }

  .wrap { max-width: 780px; margin: 0 auto; padding: 3rem 1.5rem 5rem; }
  h1 { font-size: 2.35rem; line-height: 1.18; font-weight: 700; letter-spacing: -0.015em; color: var(--brand-dark); margin-bottom: 1.4rem; margin-top: 0; }
  h2 { font-size: 1.55rem; font-weight: 700; color: var(--brand-dark); margin-top: 2.75rem; margin-bottom: 0.95rem; letter-spacing: -0.01em; }
  h3 { font-size: 1.2rem; font-weight: 700; margin-top: 1.85rem; margin-bottom: 0.55rem; color: var(--brand); }
  h4 { font-size: 1.05rem; font-weight: 700; margin-top: 1.35rem; margin-bottom: 0.45rem; color: var(--text); }
  p { margin-bottom: 1.2rem; color: var(--text-soft); }
  strong { color: var(--text); font-weight: 700; }
  em { color: var(--text-soft); }
  ul, ol { margin: 0 0 1.25rem 1.5rem; color: var(--text-soft); }
  li { margin-bottom: 0.45rem; }
  blockquote { margin: 1.75rem 0; padding: 1rem 1.4rem; background: var(--brand-soft); border-left: 3px solid var(--brand); border-radius: 0 3px 3px 0; font-style: italic; color: var(--text); }
  code { background: var(--panel); padding: 0.12rem 0.4rem; border-radius: 3px; font-family: ui-monospace, Menlo, monospace; font-size: 0.88em; color: var(--brand-dark); }
  pre { background: var(--panel); padding: 1.1rem 1.3rem; border-radius: 4px; overflow-x: auto; margin-bottom: 1.25rem; font-size: 0.9rem; border: 1px solid var(--border); }
  pre code { background: transparent; padding: 0; color: var(--text); }
  hr { border: none; border-top: 1px solid var(--border); margin: 2.5rem 0; }
  table { width: 100%; border-collapse: collapse; margin-bottom: 1.75rem; font-size: 0.94rem; }
  th, td { padding: 0.7rem 0.9rem; border-bottom: 1px solid var(--border); text-align: left; }
  th { font-size: 0.78rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--brand-dark); font-weight: 700; background: var(--panel); }
  .cta-block { margin: 3rem 0 1rem; padding: 1.85rem 1.6rem; background: var(--brand-soft); border: 1px solid rgba(0,102,143,0.2); border-radius: 5px; text-align: center; }
  .cta-block p { margin-bottom: 1.1rem; font-size: 1.06rem; color: var(--text); }
  .cta-block a { display: inline-block; padding: 0.75rem 1.6rem; background: var(--brand); color: #fff !important; border-radius: 3px; font-weight: 600; text-decoration: none; font-size: 0.95rem; transition: background 0.15s; }
  .cta-block a:hover { background: var(--brand-dark); color: #fff !important; text-decoration: none; }

  .author-card { display: flex; gap: 1rem; align-items: center; margin: 1.5rem 0 2.5rem; padding: 1rem 1.25rem; background: var(--panel); border: 1px solid var(--border); border-left: 3px solid var(--brand); border-radius: 0 4px 4px 0; }
  .author-photo { width: 52px; height: 52px; border-radius: 50%; object-fit: cover; flex-shrink: 0; }
  .author-meta { font-size: 0.9rem; line-height: 1.5; }
  .author-line { color: var(--text); }
  .author-line strong { color: var(--brand-dark); font-weight: 700; }
  .author-cred { color: var(--text-soft); font-size: 0.85rem; margin-top: 0.15rem; }
  .author-cred a { color: var(--brand); font-weight: 600; margin-left: 0.35rem; white-space: nowrap; }
  @media (max-width: 520px) {
    .author-card { flex-direction: column; align-items: flex-start; gap: 0.65rem; }
  }

  /* Breadcrumbs */
  .breadcrumbs { font-size: 0.85rem; color: var(--dim); margin: 0.5rem 0 1rem; }
  .breadcrumbs a { color: var(--brand); text-decoration: none; }
  .breadcrumbs a:hover { text-decoration: underline; }
  .breadcrumbs .sep { margin: 0 0.4rem; color: var(--border); }
  .breadcrumbs .current { color: var(--text-soft); }

  /* Related content block */
  .related-section { margin-top: 3rem; padding-top: 2rem; border-top: 1px solid var(--border); }
  .related-section h2 { font-size: 1.15rem; color: var(--brand-dark); margin-top: 0; margin-bottom: 1rem; }
  .related-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 0.75rem; }
  .related-card { background: var(--panel); border: 1px solid var(--border); border-radius: 4px; padding: 0.85rem 1rem; transition: border-color 0.15s, transform 0.15s; }
  .related-card:hover { border-color: var(--brand); transform: translateX(2px); text-decoration: none; }
  .related-card h3 { font-size: 0.95rem; font-weight: 600; color: var(--brand-dark); margin: 0 0 0.2rem; line-height: 1.3; }
  .related-card p { font-size: 0.82rem; color: var(--text-soft); margin: 0; line-height: 1.45; }
  .related-list { list-style: none; padding: 0; margin: 0; }
  .related-list li { border-bottom: 1px solid var(--border); padding: 0.6rem 0; }
  .related-list li:last-child { border-bottom: none; }
  .related-list a { color: var(--text); text-decoration: none; display: block; }
  .related-list a:hover { color: var(--brand); }