:root{
  --bg:#f7f7f7;
  --panel:#ffffff;
  --panel2:#ffffff;
  --text:#1f2937;
  --muted:#6b7280;
  --line:#e5e7eb;
  --accent:#2563eb;
  --accent2:#1d4ed8;
  --sidebar:270px;
}

*{box-sizing:border-box}
html{scroll-behavior:smooth}

body{
  margin:0;
  font-family:"Segoe UI",system-ui,-apple-system,BlinkMacSystemFont,sans-serif;
  background:var(--bg);
  color:var(--text);
  line-height:1.7;
}

a{
  color:var(--accent);
  text-decoration:none;
}
a:hover{
  text-decoration:underline;
}

.layout{
  display:grid;
  grid-template-columns:var(--sidebar) 1fr;
  min-height:100vh;
}

.sidebar{
  position:sticky;
  top:0;
  height:100vh;
  overflow-y:auto;
  background:var(--panel2);
  border-right:1px solid var(--line);
  padding:26px 22px;
}

.brand h1{
  margin:0 0 8px;
  font-size:1.18rem;
  line-height:1.2;
  color:#111;
}
.brand p{
  margin:0;
  color:var(--muted);
  font-size:.94rem;
}

.toc-title{
  margin:28px 0 14px;
  color:#1d4ed8;
  text-transform:uppercase;
  letter-spacing:.08em;
  font-size:.82rem;
  font-weight:700;
  background:#e8f1ff;
  border:1px solid #d6e6ff;
  padding:8px 12px;
  border-radius:8px;
}

.nav a{
  display:block;
  padding:10px 12px;
  margin:6px 0;
  border-radius:8px;
  color:#334155;
  font-size:1rem;
  font-weight:500;
  text-decoration:none;
  transition:background 0.18s ease, color 0.18s ease;
}

.nav a:hover{
  background:#eef4ff;
  color:#1d4ed8;
  text-decoration:none;
}

.nav a.active{
  background:#ececec;
  color:#111827;
  font-weight:600;
}

.sidebar-footer{
  margin-top:26px;
  padding-top:16px;
  border-top:1px solid var(--line);
  color:var(--muted);
  font-size:.88rem;
}

.mobile-topbar{
  display:none;
  position:sticky;
  top:0;
  z-index:10;
  background:rgba(255,255,255,.96);
  backdrop-filter:blur(10px);
  border-bottom:1px solid var(--line);
  padding:14px 16px;
  align-items:center;
  justify-content:space-between;
}

.mobile-title{
  font-weight:600;
  color:#111;
}

.menu-btn{
  font:inherit;
  color:#111;
  background:#fff;
  border:1px solid var(--line);
  border-radius:10px;
  padding:8px 12px;
}

.mobile-menu{
  display:none;
  position:sticky;
  top:57px;
  z-index:9;
  background:var(--panel2);
  border-bottom:1px solid var(--line);
  padding:10px 12px 14px;
}
.mobile-menu.open{
  display:block;
}

.mobile-menu a{
  display:block;
  padding:8px 10px;
  margin:4px 0;
  border-radius:8px;
  color:#334155;
}
.mobile-menu a.active,
.mobile-menu a:hover{
  background:rgba(0,0,0,.04);
  color:#111;
  text-decoration:none;
}

.content{
  width:100%;
  max-width:none;
  margin:0;
  padding:24px 24px 60px 28px;
  min-width:0;
}

.hero{
  margin-bottom:30px;
}

.eyebrow{
  color:var(--accent2);
  text-transform:uppercase;
  letter-spacing:.08em;
  font-size:.82rem;
  margin-bottom:10px;
  font-weight:700;
}

.hero h2{
  margin:0 0 10px;
  font-size:clamp(2rem,4vw,2.6rem);
  line-height:1.1;
  color:#111;
}

.tagline{
  font-size:1.05rem;
  color:var(--muted);
  margin:0 0 18px;
}

.summary{
  background:var(--panel);
  border:1px solid var(--line);
  border-radius:10px;
  padding:18px;
  color:var(--text);
}
.summary p{margin:0 0 10px}
.summary p:last-child{margin-bottom:0}

.links{
  display:flex;
  flex-wrap:wrap;
  gap:10px;
  margin-top:18px;
}

.button-link{
  display:inline-block;
  padding:9px 14px;
  border:1px solid #cfd6df;
  border-radius:6px;
  background:#fff;
  color:#111;
  font-size:.95rem;
}
.button-link:hover{
  background:#f3f4f6;
  text-decoration:none;
}

.doc{
  border-top:1px solid var(--line);
  padding-top:28px;
}

.doc h1{
  display:none;
}
.doc h2:first-child{
  margin-top:0;
}
.doc h2{
  color:#111;
  font-size:1.6rem;
  line-height:1.25;
  margin:30px 0 12px;
}
.doc h3{
  color:#111;
  font-size:1.08rem;
  margin:20px 0 8px;
}
.doc p{
  color:var(--text);
  margin:0 0 14px;
}
.doc ul,.doc ol{
  color:var(--text);
  margin:0 0 16px 0;
  padding-left:22px;
}
.doc li{
  margin:6px 0;
}
.doc hr{
  border:0;
  border-top:1px solid var(--line);
  margin:24px 0;
}
.doc blockquote{
  margin:16px 0;
  padding:14px 16px;
  border-left:4px solid var(--accent);
  background:#ffffff;
  border-radius:0 12px 12px 0;
  color:var(--text);
}
.doc code{
  font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  background:#f1f5f9;
  border:1px solid #dbe2ea;
  padding:2px 6px;
  border-radius:4px;
  font-size:.92em;
}
.doc pre{
  background:#f8fafc;
  border:1px solid #dbe2ea;
  padding:14px;
  border-radius:8px;
  overflow:auto;
}
.footer-note{
  margin-top:28px;
  color:var(--muted);
  font-size:.9rem;
}

@media (max-width: 860px){
  .layout{grid-template-columns:1fr}
  .sidebar{display:none}
  .mobile-topbar{display:flex}
  .content{padding:24px 18px 48px}
}