*{margin:0;padding:0;box-sizing:border-box;}
:root{
  --bg:#0a0a0a;
  --text:#ffffff;
  --muted:rgba(255,255,255,.55);
  --border:rgba(255,255,255,.12);
  --card-bg:rgba(255,255,255,.04);
  --card-border:rgba(255,255,255,.1);
  --accent:#9dd5ff;
}
html{scroll-behavior:smooth;}
body{
  background:var(--bg); color:var(--text);
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Helvetica,Arial,sans-serif;
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
}
a{color:inherit;text-decoration:none;}
code, .mono{font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;}

/* ---------- Top bar ---------- */
header.top{
  position:sticky;top:0;z-index:60;
  display:flex;align-items:center;justify-content:space-between;
  padding:14px 24px;border-bottom:1px solid var(--border);
  background:rgba(10,10,10,.85);backdrop-filter:blur(10px);
}
.top-left{display:flex;align-items:center;gap:14px;}
.top-brand{display:flex;align-items:center;gap:9px;font-weight:600;font-size:15px;}
.top-brand img{height:16px;width:auto;display:block;}
.top-brand .sep{color:var(--border);}
.top-brand .docs-word{color:var(--muted);font-weight:500;}
.top-right{display:flex;align-items:center;gap:18px;}
.top-right a{font-size:13.5px;color:var(--muted);}
.top-right a:hover{color:var(--text);}
.top-right .btn{
  background:#fff;color:var(--bg);padding:8px 16px;border-radius:8px;
  font-size:13.5px;font-weight:600;
}

/* ---------- Layout ---------- */
.shell{display:grid;grid-template-columns:250px 1fr 200px;max-width:1400px;margin:0 auto;}

nav.side{
  position:sticky;top:53px;align-self:start;
  height:calc(100vh - 53px);overflow-y:auto;
  padding:28px 16px 60px;border-right:1px solid var(--border);
  font-size:13.5px;
}
nav.side .grp{margin-bottom:4px;}
nav.side .grp-row{display:flex;align-items:stretch;border-radius:6px;}
nav.side .grp-row:hover{background:var(--card-bg);}
nav.side .grp-link{
  flex:1;display:block;color:var(--muted);padding:8px 4px 8px 10px;font-weight:600;
}
nav.side .grp-row.current .grp-link{color:var(--text);}
nav.side .grp-toggle{
  background:none;border:0;color:var(--muted);cursor:pointer;padding:0 10px;
  display:flex;align-items:center;
}
nav.side .grp-toggle svg{transition:transform .18s ease;}
nav.side .grp.open .grp-toggle svg{transform:rotate(90deg);}
nav.side .grp-toggle:hover{color:var(--text);}
nav.side .grp-children{
  display:grid;grid-template-rows:0fr;transition:grid-template-rows .2s ease;
  margin-left:8px;padding-left:10px;border-left:1px solid var(--border);
}
nav.side .grp.open .grp-children{grid-template-rows:1fr;}
nav.side .grp-children-inner{overflow:hidden;}
nav.side .grp-children a{
  display:block;color:var(--muted);padding:7px 10px;border-radius:6px;margin:1px 0;
}
nav.side .grp-children a:hover{color:var(--text);background:var(--card-bg);}
nav.side .grp-children a.active{color:var(--text);background:var(--card-bg);}
nav.side .single a{
  display:block;color:var(--muted);padding:8px 10px;border-radius:6px;font-weight:600;margin-bottom:1px;
}
nav.side .single a:hover{color:var(--text);background:var(--card-bg);}
nav.side .single a.active{color:var(--text);background:var(--card-bg);}
nav.side .grp-section-label{
  color:var(--muted);font-size:11px;font-weight:600;letter-spacing:.4px;
  margin:20px 0 8px 10px;
}
nav.side .grp-section-label:first-child{margin-top:0;}

main.content{padding:48px 48px 140px;min-width:0;}
.doc-section{margin-bottom:56px;scroll-margin-top:72px;}
.doc-section:last-child{margin-bottom:0;}
.kicker{
  font-size:11.5px;font-weight:600;letter-spacing:.5px;color:var(--accent);
  margin-bottom:10px;
}
h1.page-title{font-size:36px;font-weight:600;letter-spacing:-.02em;margin-bottom:16px;}
.lede{color:var(--muted);font-size:17px;line-height:1.6;max-width:700px;margin-bottom:8px;}

h2{font-size:23px;font-weight:600;letter-spacing:-.01em;margin:0 0 16px;scroll-margin-top:72px;}
h3{font-size:17px;font-weight:600;margin:26px 0 10px;scroll-margin-top:72px;}
.doc-section h3 a{color:inherit;text-decoration:none;}
.doc-section h3 a:hover{color:var(--accent);text-decoration:underline;text-decoration-color:rgba(157,213,255,.4);text-underline-offset:3px;}
p{color:var(--muted);font-size:15px;line-height:1.75;max-width:700px;margin-bottom:16px;}
p strong, li strong{color:var(--text);font-weight:600;}
p code, li code{
  background:var(--card-bg);border:1px solid var(--card-border);border-radius:5px;
  padding:1.5px 6px;font-size:13.5px;color:var(--text);
}
ul.plain{margin:0 0 18px 20px;max-width:700px;}
ul.plain li{color:var(--muted);font-size:15px;line-height:1.75;margin-bottom:8px;}
ol.steps{margin:0 0 18px 20px;max-width:700px;}
ol.steps li{color:var(--muted);font-size:15px;line-height:1.75;margin-bottom:10px;}

.sub-breadcrumb{margin-bottom:16px;font-size:13px;}
.sub-breadcrumb a{color:var(--muted);}
.sub-breadcrumb a:hover{color:var(--text);}

.page-covers{margin:4px 0 30px;max-width:700px;}
.page-covers .covers-label{color:var(--text);font-weight:600;font-size:14px;margin-bottom:12px;}
.page-covers ul{margin:0;padding:0;list-style:none;}
.page-covers li{position:relative;padding-left:18px;margin-bottom:10px;color:var(--muted);font-size:14.5px;line-height:1.65;}
.page-covers li::before{content:"";position:absolute;left:2px;top:9px;width:4px;height:4px;border-radius:50%;background:var(--muted);}
.page-covers a{color:var(--text);font-weight:600;text-decoration:underline;text-decoration-color:rgba(255,255,255,.25);text-underline-offset:2px;}
.page-covers a:hover{text-decoration-color:var(--text);}

.callout{
  display:flex;gap:12px;align-items:flex-start;
  border:1px solid rgba(157,213,255,.25);background:rgba(157,213,255,.08);border-radius:10px;
  padding:14px 18px;margin:0 0 22px;max-width:700px;
}
.callout .callout-icon{flex-shrink:0;color:var(--accent);margin-top:2px;}
.callout .callout-body{min-width:0;}
.callout .callout-label{font-size:11.5px;font-weight:700;letter-spacing:.4px;color:var(--accent);margin-bottom:4px;}
.callout p{margin-bottom:0;color:var(--text);opacity:.85;}

/* ---------- Top tab bar ---------- */
.tab-bar{border-bottom:1px solid var(--border);overflow-x:auto;}
.tab-bar-inner{display:flex;gap:4px;padding:0 24px;max-width:1400px;margin:0 auto;}
.tab-bar-inner a{
  display:block;padding:13px 14px;font-size:13.5px;color:var(--muted);
  border-bottom:2px solid transparent;white-space:nowrap;
}
.tab-bar-inner a:hover{color:var(--text);}
.tab-bar-inner a.active{color:var(--text);border-bottom-color:var(--text);font-weight:600;}

/* ---------- Page title row + copy button ---------- */
.page-title-row{display:flex;align-items:flex-start;justify-content:space-between;gap:16px;flex-wrap:wrap;}
.copy-page-btn{
  display:flex;align-items:center;gap:7px;flex-shrink:0;margin-top:2px;
  background:var(--card-bg);border:1px solid var(--card-border);border-radius:8px;
  padding:8px 12px;color:var(--muted);font-size:13px;cursor:pointer;
}
.copy-page-btn:hover{color:var(--text);border-color:rgba(255,255,255,.25);}

/* ---------- Ask CTA ---------- */
.ask-cta{
  display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:12px;
  border:1px solid var(--card-border);background:var(--card-bg);border-radius:12px;
  padding:18px 22px;margin:48px 0 0;max-width:700px;
}
.ask-cta span{color:var(--muted);font-size:14px;}
.ask-cta a{color:var(--text);font-size:14px;font-weight:600;}
.ask-cta a:hover{opacity:.75;}

pre.code-block{
  background:#0d0d0d;border:1px solid var(--card-border);border-radius:10px;
  padding:16px 18px;margin:0 0 20px;overflow-x:auto;max-width:720px;
  font-size:13.5px;line-height:1.7;color:rgba(255,255,255,.85);
  white-space:pre-wrap;word-break:break-word;
}
pre.code-block .c1{color:rgba(255,255,255,.4);}
pre.code-block .kw{color:var(--accent);}
pre.code-block .ok{color:#8fe3a8;}

table.ref{width:100%;max-width:820px;border-collapse:collapse;margin:0 0 24px;font-size:14px;}
table.ref th, table.ref td{text-align:left;padding:10px 16px 10px 0;border-bottom:1px solid var(--border);vertical-align:top;}
table.ref th{color:var(--muted);font-weight:600;font-size:12px;letter-spacing:.3px;}
table.ref td{color:var(--muted);}
table.ref td code{white-space:nowrap;}
table.ref td.name{color:var(--text);font-weight:600;white-space:nowrap;}

.card-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:16px;margin:0 0 24px;max-width:760px;}
.mini-card{border:1px solid var(--card-border);border-radius:12px;padding:20px;}
.mini-card h4{font-size:14.5px;font-weight:600;margin-bottom:8px;}
.mini-card p{font-size:13.5px;margin-bottom:0;}
@media (max-width:720px){.card-grid{grid-template-columns:1fr;}}

.page-pager{
  display:flex;align-items:center;justify-content:space-between;gap:16px;
  border-top:1px solid var(--border);padding-top:24px;margin-top:56px;max-width:820px;
}
.page-pager a{
  border:1px solid var(--card-border);border-radius:10px;padding:12px 18px;
  font-size:13.5px;color:var(--muted);flex:1;
}
.page-pager a:hover{color:var(--text);border-color:rgba(255,255,255,.3);}
.page-pager a.next{text-align:right;}
.page-pager .pager-label{display:block;font-size:11px;color:var(--muted);margin-bottom:4px;letter-spacing:.3px;}
.page-pager a .pager-title{color:var(--text);font-weight:600;}

nav.toc{position:sticky;top:53px;align-self:start;height:calc(100vh - 53px);overflow-y:auto;padding:32px 0 40px;font-size:13px;}
nav.toc .toc-h{color:var(--muted);font-weight:600;font-size:11.5px;letter-spacing:.4px;margin-bottom:12px;}
nav.toc a{
  display:block;color:var(--muted);padding:5px 0 5px 12px;
  border-left:2px solid transparent;margin-bottom:1px;
}
nav.toc a:hover{color:var(--text);}
nav.toc a.active{color:var(--text);border-left-color:var(--accent);}
nav.toc a.sub{padding-left:24px;font-size:12.5px;}

@media (max-width:1100px){
  .shell{grid-template-columns:230px 1fr;}
  nav.toc{display:none;}
}
@media (max-width:820px){
  .shell{grid-template-columns:1fr;}
  nav.side{position:static;height:auto;border-right:0;border-bottom:1px solid var(--border);padding:20px 16px;}
  main.content{padding:36px 20px 100px;}
}

/* ---------- Search ---------- */
.search-btn{
  display:flex;align-items:center;gap:8px;
  background:var(--card-bg);border:1px solid var(--card-border);border-radius:8px;
  padding:8px 10px 8px 12px;cursor:pointer;color:var(--muted);
  font-size:13.5px;width:260px;max-width:36vw;
}
.search-btn:hover{border-color:rgba(255,255,255,.25);color:var(--text);}
.search-btn span{flex:1;text-align:left;}
.search-btn kbd{
  font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  font-size:11px;color:var(--muted);border:1px solid var(--card-border);border-radius:4px;
  padding:1px 5px;
}
@media (max-width:720px){.search-btn{display:none;}}

.search-overlay{
  display:none;position:fixed;inset:0;z-index:100;
  background:rgba(0,0,0,.6);
  align-items:flex-start;justify-content:center;
  padding:12vh 20px 0;
}
.search-overlay.open{display:flex;}
.search-modal{
  width:100%;max-width:560px;
  background:#111;border:1px solid var(--card-border);border-radius:14px;
  box-shadow:0 30px 80px rgba(0,0,0,.5);
  overflow:hidden;
}
.search-modal input{
  width:100%;background:none;border:0;border-bottom:1px solid var(--border);
  padding:16px 18px;color:var(--text);font-size:16px;outline:none;
}
.search-modal input::placeholder{color:var(--muted);}
.search-results{max-height:50vh;overflow-y:auto;padding:8px;}
.search-results a{
  display:block;padding:10px 12px;border-radius:8px;margin-bottom:2px;
}
.search-results a:hover, .search-results a.sel{background:var(--card-bg);}
.search-results .r-title{color:var(--text);font-size:14px;font-weight:600;margin-bottom:2px;}
.search-results .r-section{color:var(--accent);font-size:11px;font-weight:600;letter-spacing:.3px;margin-bottom:3px;}
.search-results .r-snippet{color:var(--muted);font-size:12.5px;line-height:1.5;}
.search-empty{padding:24px 18px;color:var(--muted);font-size:13.5px;text-align:center;}

/* ---------- Diagrams ---------- */
.diagram-card{
  border:1px solid var(--card-border);background:var(--card-bg);border-radius:14px;
  padding:24px;margin:0 0 26px;max-width:760px;overflow-x:auto;
}
.diagram-card svg{display:block;min-width:640px;}
.diagram-caption{color:var(--muted);font-size:12.5px;margin-top:12px;text-align:center;}

/* ---------- Effort scale ---------- */
.effort-scale{display:flex;gap:12px;margin:0 0 26px;max-width:700px;}
.effort-scale .lvl{
  flex:1;border:1px solid var(--card-border);border-radius:12px;padding:16px 18px;
}
.effort-scale .lvl .bar{height:4px;border-radius:2px;margin-bottom:12px;background:var(--card-border);}
.effort-scale .lvl.low .bar{background:linear-gradient(90deg,var(--accent) 33%,var(--card-border) 33%);}
.effort-scale .lvl.medium .bar{background:linear-gradient(90deg,var(--accent) 66%,var(--card-border) 66%);}
.effort-scale .lvl.high .bar{background:var(--accent);}
.effort-scale .lvl h4{font-size:13.5px;font-weight:600;margin-bottom:4px;}
.effort-scale .lvl p{font-size:12.5px;margin-bottom:0;}
@media (max-width:640px){.effort-scale{flex-direction:column;}}