:root{
  --bg:#ffffff;
  --paper:#fbfbfa;
  --ink:#111827;
  --muted:#6b7280;
  --line:#e5e7eb;
  --accent:#f28c28;
  --radius:18px;
}

*{box-sizing:border-box}
html,body{height:100%}
body{
  margin:0;
  font-family: ui-serif, Georgia, Cambria, "Times New Roman", Times, serif;
  color:var(--ink);
  background: linear-gradient(180deg, var(--bg), var(--paper));
}

a{color:inherit}
.container{max-width: 920px; margin: 0 auto; padding: 0 18px;}
.topbar{
  position: sticky; top: 0; z-index: 20;
  background: rgba(255,255,255,.86);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.topbar .row{
  display:flex; align-items:center; justify-content:space-between;
  gap:16px; padding: 12px 0;
}
.brand{
  display:flex; align-items:center; gap:12px; text-decoration:none;
}
.brand img{width:34px; height:34px; object-fit:contain}
.brand .name{
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  font-weight: 700; letter-spacing: .2px;
}
.brand .tag{
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  color:var(--muted); font-size: 12px;
}

.nav{
  display:flex; gap:14px; align-items:center;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  font-size: 13px;
}
.nav a{
  text-decoration:none;
  padding:8px 10px;
  border-radius: 12px;
  border: 1px solid transparent;
  color: var(--muted);
}
.nav a:hover{border-color: var(--line); color: var(--ink)}
.nav a.primary{
  color: var(--ink);
  border-color: rgba(242,140,40,.25);
  background: rgba(242,140,40,.06);
}

.hero{
  padding: 34px 0 10px;
}
.kicker{
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  color: var(--muted);
  letter-spacing: .12em;
  text-transform: uppercase;
  font-size: 12px;
}
h1{
  margin: 10px 0 6px;
  font-size: 40px;
  line-height: 1.05;
  letter-spacing: -0.02em;
}
.subtitle{
  margin: 0;
  color: var(--muted);
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  font-size: 14px;
}
.rule{
  margin: 22px 0 0;
  height: 1px;
  background: linear-gradient(90deg, rgba(242,140,40,.65), rgba(229,231,235,0));
}

.paper{
  margin: 18px 0 60px;
  padding: 22px 22px 26px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: 0 10px 30px rgba(17,24,39,.06);
}

.paper h2{
  margin: 26px 0 10px;
  font-size: 22px;
  line-height: 1.25;
}
.paper h3{
  margin: 18px 0 8px;
  font-size: 18px;
  line-height: 1.3;
}
.paper h4{
  margin: 14px 0 6px;
  font-size: 16px;
  line-height: 1.3;
}
.paper p{
  margin: 0 0 12px;
  font-size: 18px;
  line-height: 1.72;
}

.paper h2::before{
  content:"";
  display:inline-block;
  width:10px; height:10px;
  border-radius: 999px;
  background: var(--accent);
  margin-right:10px;
  transform: translateY(-1px);
}

.illus{
  margin: 18px 0 22px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}
.illus img{
  width:100%;
  height:auto;
  display:block;
  border-radius: 14px;
}

.footer{
  border-top: 1px solid var(--line);
  padding: 18px 0 28px;
  color: var(--muted);
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  font-size: 13px;
}
.meta{
  display:flex; gap:12px; flex-wrap:wrap;
  align-items:center; justify-content:space-between;
}
.badge{
  display:inline-flex; gap:8px; align-items:center;
  padding: 6px 10px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: rgba(242,140,40,.05);
  color: var(--ink);
}
.dot{width:7px;height:7px;border-radius:999px;background:var(--accent)}

@media (max-width: 640px){
  h1{font-size: 32px}
  .paper{padding: 18px 16px}
  .paper p{font-size: 17px}
  .nav{display:none}
}


/* Docs layout */
.docs-wrap{
  display:grid;
  grid-template-columns: 260px 1fr;
  gap:18px;
  align-items:start;
}
.toc{
  position: sticky;
  top: 74px;
  border:1px solid var(--line);
  border-radius: var(--radius);
  padding: 14px 12px;
  background:#fff;
}
.toc .toc-title{
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  font-weight:700;
  font-size: 13px;
  margin: 0 0 10px;
  letter-spacing:.02em;
}
.toc a{
  display:block;
  text-decoration:none;
  color: var(--muted);
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  font-size: 12.5px;
  padding: 6px 8px;
  border-radius: 10px;
  border: 1px solid transparent;
}
.toc a:hover{border-color: var(--line); color: var(--ink)}
.toc a.l2{padding-left:8px}
.toc a.l3{padding-left:18px}
.toc a.l4{padding-left:28px}

.doc-title{
  margin: 0 0 4px;
  font-size: 30px;
  letter-spacing: -0.02em;
  line-height: 1.1;
}
.doc-meta{
  margin: 0 0 16px;
  color: var(--muted);
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  font-size: 13px;
}
.doc-actions{
  display:flex; gap:10px; flex-wrap:wrap;
  margin: 10px 0 0;
}
.chip{
  display:inline-flex; align-items:center; gap:8px;
  padding: 7px 10px;
  border-radius: 999px;
  border:1px solid var(--line);
  background: #fff;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  font-size: 12.5px;
  color: var(--ink);
  text-decoration:none;
}
.chip:hover{border-color: rgba(242,140,40,.35)}
.chip .dot{width:7px;height:7px;border-radius:999px;background:var(--accent)}
.docs-list{
  display:grid;
  grid-template-columns: repeat(2, 1fr);
  gap:14px;
}
.cardlink{
  display:block;
  text-decoration:none;
  border:1px solid var(--line);
  border-radius: var(--radius);
  padding: 14px 14px 12px;
  background:#fff;
  box-shadow: 0 10px 30px rgba(17,24,39,.04);
}
.cardlink:hover{border-color: rgba(242,140,40,.35)}
.cardlink h3{
  margin:0 0 6px;
  font-size:16px;
}
.cardlink p{
  margin:0;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.5;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
}
@media (max-width: 900px){
  .docs-wrap{grid-template-columns: 1fr;}
  .toc{position:relative; top:auto}
  .docs-list{grid-template-columns: 1fr;}
}