:root{
    --navy:#14263F;
    --navy-2:#1E3A5F;
    --navy-soft:#274B78;
    --red:#C8102E;
    --red-soft:#FDEBED;
    --gold:#B8860B;
    --gold-soft:#FBF3DF;
    --ink:#24303E;
    --muted:#5A6B7C;
    --bg:#FFFFFF;
    --bg-soft:#F4F6F9;
    --line:#E2E7EE;
    --green:#1E7A4F;
    --green-soft:#EAF6F0;
    --radius:10px;
    --shadow:0 10px 30px rgba(20,38,63,.10);
  }
  *{box-sizing:border-box;margin:0;padding:0;}
  html{scroll-behavior:smooth;}
  body{
    font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,"Noto Sans",sans-serif;
    color:var(--ink);
    background:var(--bg);
    line-height:1.65;
    font-size:16.5px;
    -webkit-font-smoothing:antialiased;
  }
  a{color:var(--navy-soft);text-decoration:none;}
  a:hover{text-decoration:underline;}

  /* ---------- Top bar ---------- */
  .topbar{
    position:sticky;top:0;z-index:50;
    background:rgba(20,38,63,.97);
    color:#fff;
    box-shadow:0 2px 12px rgba(0,0,0,.18);
    backdrop-filter:blur(6px);
  }
  .topbar-inner{
    max-width:1080px;margin:0 auto;padding:10px 24px;
    display:flex;align-items:center;gap:14px;
  }
  .topbar .logo{height:38px;width:auto;display:block;filter:drop-shadow(0 1px 2px rgba(0,0,0,.3));}
  .topbar .brand{font-size:15px;font-weight:700;letter-spacing:.3px;line-height:1.2;}
  .topbar .brand small{display:block;font-weight:400;font-size:12px;color:#C9D4E3;}
  .topbar .chapter-chip{
    margin-left:auto;font-size:12px;font-weight:700;letter-spacing:.8px;
    background:var(--red);color:#fff;padding:5px 12px;border-radius:999px;white-space:nowrap;
  }
  @media (max-width:640px){ .topbar .brand small{display:none;} }

  /* ---------- Hero ---------- */
  .hero{
    background:linear-gradient(180deg,#F7F9FC 0%,#FFFFFF 100%);
    border-bottom:1px solid var(--line);
    padding:44px 24px 40px;
  }
  .hero-inner{
    max-width:1080px;margin:0 auto;
    display:grid;grid-template-columns:380px 1fr;gap:40px;align-items:center;
  }
  .hero-cover{
    border-radius:var(--radius);overflow:hidden;
    box-shadow:var(--shadow);border:1px solid var(--line);
    background:#fff;
  }
  .hero-cover img{display:block;width:100%;height:auto;}
  .hero-kicker{
    color:var(--gold);font-weight:800;letter-spacing:2.5px;font-size:13px;text-transform:uppercase;
  }
  .hero-chip{
    display:inline-block;margin-top:12px;background:var(--red);color:#fff;
    font-size:13px;font-weight:700;letter-spacing:1px;padding:5px 14px;border-radius:6px;
  }
  .hero h1{
    font-size:clamp(30px,4.6vw,46px);line-height:1.12;color:var(--navy);
    margin:16px 0 10px;font-weight:800;letter-spacing:-.5px;
  }
  .hero .hero-sub{
    font-size:15px;font-weight:700;letter-spacing:2.5px;color:var(--navy-2);text-transform:uppercase;
  }
  .hero .hero-co{
    margin-top:14px;color:var(--muted);font-size:14px;
  }
  .hero-strap{
    margin-top:22px;display:flex;gap:8px;flex-wrap:wrap;
  }
  .hero-strap span{
    font-size:12px;font-weight:700;letter-spacing:1.2px;color:var(--navy);
    border:1px solid var(--line);background:#fff;padding:6px 14px;border-radius:999px;
  }
  @media (max-width:860px){
    .hero-inner{grid-template-columns:1fr;gap:26px;}
    .hero-cover{max-width:420px;margin:0 auto;}
  }

  /* ---------- Layout ---------- */
  .wrap{max-width:1080px;margin:0 auto;padding:36px 24px 60px;}
  .grid{display:grid;grid-template-columns:240px minmax(0,1fr);gap:40px;align-items:start;}
  @media (max-width:960px){ .grid{grid-template-columns:1fr;} }

  /* ---------- TOC ---------- */
  .toc{
    position:sticky;top:86px;
    background:var(--bg-soft);border:1px solid var(--line);border-radius:var(--radius);
    padding:18px 18px 14px;font-size:14px;
  }
  .toc h2{font-size:13px;text-transform:uppercase;letter-spacing:1.5px;color:var(--muted);margin-bottom:10px;}
  .toc ol{list-style:none;counter-reset:sec;}
  .toc li{margin:2px 0;}
  .toc a{
    display:block;padding:4px 8px;border-radius:6px;color:var(--ink);
    counter-increment:sec;
  }
  .toc a::before{content:counter(sec,decimal-leading-zero);font-weight:700;color:var(--red);margin-right:8px;font-size:12px;}
  .toc a:hover{background:#fff;text-decoration:none;color:var(--navy-soft);}
  .toc .toc-objs a::before{content:"◆";color:var(--gold);font-size:9px;}
  @media (max-width:960px){ .toc{position:static;} }

  /* ---------- Content blocks ---------- */
  article{min-width:0;}
  section{margin-bottom:44px;scroll-margin-top:74px;}
  .sec-head{display:flex;align-items:baseline;gap:14px;margin-bottom:12px;}
  .sec-num{
    flex:none;min-width:44px;height:44px;border-radius:8px;
    background:var(--red);color:#fff;font-weight:800;font-size:20px;
    display:flex;align-items:center;justify-content:center;
    box-shadow:0 4px 12px rgba(200,16,46,.28);
  }
  .sec-head h2{font-size:24px;color:var(--navy);font-weight:800;letter-spacing:-.2px;line-height:1.25;}
  .sec-head .kicker{font-size:12px;font-weight:700;letter-spacing:1.6px;color:var(--muted);text-transform:uppercase;}
  h3{
    font-size:18.5px;color:var(--navy-2);font-weight:750;
    margin:26px 0 8px;padding-left:12px;border-left:4px solid var(--gold);
  }
  p{margin:0 0 14px;}
  ul,ol{margin:0 0 16px 6px;padding-left:22px;}
  li{margin:5px 0;}
  .ref{color:var(--muted);font-size:13.5px;}

  /* callouts */
  .callout{border-radius:var(--radius);padding:18px 20px;margin:20px 0;font-size:15.5px;border:1px solid;}
  .callout .c-title{font-weight:800;letter-spacing:.4px;text-transform:uppercase;font-size:13px;display:flex;align-items:center;gap:8px;margin-bottom:6px;}
  .callout p:last-child{margin-bottom:0;}
  .callout.safety{background:var(--red-soft);border-color:#F3C1C8;color:#6E1420;}
  .callout.safety .c-title{color:var(--red);}
  .callout.scope{background:var(--bg-soft);border-color:var(--line);color:var(--ink);}
  .callout.scope .c-title{color:var(--navy-2);}
  .callout.note{background:var(--gold-soft);border-color:#E8D49B;color:#6B5410;}
  .callout.note .c-title{color:var(--gold);}

  /* figures */
  figure{
    background:#fff;border:1px solid var(--line);border-radius:var(--radius);
    padding:14px;margin:22px 0;box-shadow:0 4px 14px rgba(20,38,63,.06);
  }
  figure img{display:block;width:100%;height:auto;border-radius:6px;}
  figcaption{
    margin-top:10px;font-size:13.5px;color:var(--muted);
    border-top:1px dashed var(--line);padding-top:10px;
  }
  figcaption strong{color:var(--navy);}

  /* tables */
  .tbl-wrap{overflow-x:auto;margin:18px 0;border:1px solid var(--line);border-radius:var(--radius);box-shadow:0 4px 14px rgba(20,38,63,.06);}
  table{width:100%;border-collapse:collapse;font-size:14.8px;min-width:560px;}
  thead th{
    background:var(--navy);color:#fff;text-align:left;
    padding:12px 14px;font-size:13px;text-transform:uppercase;letter-spacing:.6px;
  }
  tbody td{padding:12px 14px;border-top:1px solid var(--line);vertical-align:top;}
  tbody tr:nth-child(even){background:var(--bg-soft);}
  tbody tr:hover{background:#EAF1F9;}
  td.prop{font-weight:700;color:var(--navy);white-space:nowrap;}

  /* workflow list */
  ol.flow{counter-reset:flow;list-style:none;padding-left:0;}
  ol.flow li{
    counter-increment:flow;position:relative;padding:10px 14px 10px 58px;
    background:var(--bg-soft);border:1px solid var(--line);border-radius:8px;margin:8px 0;
  }
  ol.flow li::before{
    content:counter(flow);position:absolute;left:14px;top:50%;transform:translateY(-50%);
    width:30px;height:30px;border-radius:50%;background:var(--navy);color:#fff;
    display:flex;align-items:center;justify-content:center;font-weight:700;font-size:14px;
  }

  .matrix-note{font-style:italic;color:var(--muted);font-size:14px;}

  /* footer */
  footer{
    background:var(--navy);color:#C9D4E3;
    padding:44px 24px 30px;margin-top:30px;
  }
  .foot-inner{max-width:1080px;margin:0 auto;display:flex;flex-wrap:wrap;gap:24px;align-items:center;justify-content:space-between;}
  .foot-brand{font-size:17px;font-weight:800;color:#fff;letter-spacing:.4px;}
  .foot-strap{font-size:12.5px;letter-spacing:2.2px;font-weight:700;color:#F0B429;}
  .foot-co{font-size:13.5px;}
  .foot-co a{color:#fff;text-decoration:underline;}
  .foot-line{margin-top:24px;border-top:1px solid rgba(255,255,255,.15);padding-top:16px;font-size:12.5px;color:#8FA3BA;text-align:center;}

  /* back to top */
  #toTop{
    position:fixed;right:22px;bottom:22px;z-index:60;
    background:var(--red);color:#fff;border:none;border-radius:50%;
    width:46px;height:46px;font-size:20px;cursor:pointer;
    box-shadow:0 6px 18px rgba(200,16,46,.4);display:none;align-items:center;justify-content:center;
  }
  #toTop.show{display:flex;}

  @media (max-width:640px){
    body{font-size:16px;}
    .sec-head h2{font-size:20px;}
    .sec-num{min-width:38px;height:38px;font-size:17px;}
    table{min-width:480px;font-size:13.8px;}
    thead th{padding:10px 10px;font-size:12px;}
    tbody td{padding:10px;}
  }

  /* ---------- Print ---------- */
  @media print{
    .topbar,#toTop,.toc{display:none !important;}
    body{font-size:12px;}
    .hero{padding:10px 0;border:none;}
    .hero-inner{grid-template-columns:1fr;gap:12px;}
    .grid{grid-template-columns:1fr;}
    figure{break-inside:avoid;}
    section{break-inside:auto;}
    a{color:inherit;}
    .wrap{padding:10px 0;}
  }

/* Crawlable chapter navigation and related resources */
.breadcrumbs,.chapter-nav,.related-chapters{max-width:1080px;margin-left:auto;margin-right:auto;padding-left:24px;padding-right:24px}
.breadcrumbs{display:flex;gap:8px;align-items:center;padding-top:14px;font-size:13px;color:var(--muted)}
.breadcrumbs span:last-child{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.chapter-nav{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:8px;padding-top:12px;padding-bottom:12px}
.chapter-nav a{display:flex;align-items:center;justify-content:center;min-height:42px;padding:8px 10px;border:1px solid var(--line);border-radius:8px;background:#fff;color:var(--navy);font-size:13px;font-weight:700;line-height:1.3;text-align:center}
.chapter-nav a:hover{background:var(--bg-soft);text-decoration:none}
.chapter-nav .nav-pdf{background:var(--red);border-color:var(--red);color:#fff}
.chapter-nav--bottom{margin-top:18px;margin-bottom:22px}
.related-chapters{margin-top:8px;margin-bottom:8px}
.related-chapters h2{font-size:20px;color:var(--navy);margin-bottom:10px}
.related-chapters ul{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px;list-style:none;margin:0;padding:0}
.related-chapters li{margin:0}
.related-chapters a{display:block;height:100%;padding:12px 14px;border:1px solid var(--line);border-radius:8px;background:var(--bg-soft);font-size:14px;font-weight:700}
@media(max-width:760px){.chapter-nav{grid-template-columns:1fr 1fr}.related-chapters ul{grid-template-columns:1fr}.breadcrumbs{align-items:flex-start}.breadcrumbs span:last-child{white-space:normal}}