:root {
  --primary: #006BFF;
  --primary-dark: #0052cc;
  --primary-light: #e8f1ff;
  --fg: #0B3558;
  --fg-soft: #476788;
  --bg: #ffffff;
  --surface: #F8F9FB;
  --border: #E5E7EB;
  --border-light: #F0F3F8;
  --card: #ffffff;
  --code-bg: #0B1B3A;
  --code-fg: #E6EDF7;
  --radius: 10px;
  --radius-pill: 999px;
  --shadow-sm: 0 1px 3px rgba(11, 53, 88, 0.06);
  --shadow-md: 0 6px 18px rgba(11, 53, 88, 0.08);
  --font: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  --font-mono: ui-monospace, 'JetBrains Mono', Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  color: var(--fg);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--primary); text-decoration: none; }
a:hover { color: var(--primary-dark); text-decoration: underline; }
img, svg { max-width: 100%; vertical-align: middle; }
::selection { background: rgba(0,107,255,.15); color: var(--fg); }

/* ── Navbar ───────────────────────────────────────── */
.nav {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(255,255,255,.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
}
.nav-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  gap: 24px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 18px;
  color: var(--fg);
}
.brand:hover { text-decoration: none; }
.brand .dot { color: var(--primary); }
.brand-icon {
  width: 30px;
  height: 30px;
  flex-shrink: 0;
  border-radius: 7px;
  transition: transform .15s ease;
}
.brand:hover .brand-icon { transform: scale(1.05); }
.brand-text { white-space: nowrap; }
.brand-sub {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .04em;
  text-transform: uppercase;
  color: var(--primary);
  background: var(--primary-light);
  padding: 4px 8px;
  border-radius: var(--radius-pill);
  margin-left: 6px;
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-left: auto;
  flex-wrap: wrap;
}
.nav-links a {
  color: var(--fg-soft);
  font-size: 14px;
  font-weight: 500;
  padding: 8px 12px;
  border-radius: 8px;
}
.nav-links a:hover { color: var(--fg); background: var(--surface); text-decoration: none; }
.nav-links a.active { color: var(--primary); }
.nav-links a.btn-primary, .nav-links a.btn-primary:hover { color: #fff; }
.nav-links a.btn-outline { color: var(--fg); }
.nav-links a.btn-outline:hover { color: var(--primary); }
.btn-primary, .btn-outline {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 14px;
  font-weight: 600;
  padding: 8px 16px;
  border-radius: var(--radius-pill);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all .15s ease;
}
.btn-primary {
  background: var(--primary);
  color: #fff;
}
.btn-primary:hover { background: var(--primary-dark); color: #fff; text-decoration: none; }
.btn-outline {
  background: transparent;
  color: var(--fg);
  border-color: var(--border);
}
.btn-outline:hover { border-color: var(--primary); color: var(--primary); text-decoration: none; }
.btn-sm { padding: 6px 12px; font-size: 13px; }

/* ── Hero ─────────────────────────────────────────── */
.hero {
  padding: 80px 24px 56px;
  text-align: center;
  background:
    radial-gradient(900px 400px at 50% -20%, rgba(0,107,255,.10), transparent 60%),
    var(--bg);
}
.hero .badge {
  display: inline-block;
  padding: 6px 14px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--primary);
  background: var(--primary-light);
  border: 1px solid rgba(0,107,255,.18);
  border-radius: var(--radius-pill);
  margin-bottom: 20px;
}
.hero h1 {
  margin: 0 0 16px;
  font-size: clamp(32px, 5vw, 52px);
  font-weight: 700;
  letter-spacing: -.02em;
  line-height: 1.1;
  color: var(--fg);
}
.hero .grad { background: linear-gradient(135deg, var(--primary), #6B9FFF); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.hero p.lede {
  font-size: 18px;
  color: var(--fg-soft);
  max-width: 640px;
  margin: 0 auto 32px;
}
.hero .actions { display: inline-flex; gap: 12px; flex-wrap: wrap; justify-content: center; }

/* ── Layout ───────────────────────────────────────── */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}
.layout {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 40px;
  max-width: 1200px;
  margin: 32px auto;
  padding: 0 24px 80px;
}
@media (max-width: 900px) {
  .layout { grid-template-columns: 1fr; gap: 16px; padding-top: 12px; }
}
.sidebar {
  align-self: start;
  position: sticky;
  top: 80px;
  border-right: 1px solid var(--border-light);
  padding-right: 16px;
}
@media (max-width: 900px) {
  .sidebar { position: static; border-right: none; padding-right: 0; padding-bottom: 8px; border-bottom: 1px solid var(--border-light); }
}
.sidebar h4 {
  margin: 20px 0 8px;
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--fg-soft);
}
.sidebar h4:first-child { margin-top: 0; }
.sidebar a {
  display: block;
  padding: 6px 10px;
  font-size: 14px;
  color: var(--fg-soft);
  border-radius: 6px;
  font-weight: 500;
}
.sidebar a:hover { background: var(--surface); color: var(--fg); text-decoration: none; }
.sidebar a.active { background: var(--primary-light); color: var(--primary); font-weight: 600; }

.content { min-width: 0; }
.content h1 { font-size: 36px; line-height: 1.15; margin: 0 0 8px; font-weight: 700; letter-spacing: -.01em; }
.content h2 { font-size: 22px; margin: 40px 0 12px; font-weight: 700; padding-top: 12px; border-top: 1px solid var(--border-light); }
.content h2:first-of-type { border-top: 0; padding-top: 0; }
.content h3 { font-size: 17px; margin: 28px 0 10px; font-weight: 600; }
.content p { margin: 0 0 14px; color: var(--fg); }
.content p.lede { font-size: 17px; color: var(--fg-soft); margin-bottom: 24px; }
.content ul, .content ol { padding-left: 22px; margin: 0 0 16px; }
.content li { margin: 6px 0; }
.content code { font-family: var(--font-mono); font-size: 13px; background: var(--surface); padding: 2px 6px; border-radius: 4px; border: 1px solid var(--border-light); }
.content pre { background: var(--code-bg); color: var(--code-fg); padding: 16px 18px; border-radius: var(--radius); overflow-x: auto; margin: 0 0 18px; font-family: var(--font-mono); font-size: 13px; line-height: 1.55; }
.content pre code { background: transparent; padding: 0; border: 0; color: inherit; font-size: 13px; }
.content blockquote { margin: 0 0 16px; padding: 12px 16px; border-left: 3px solid var(--primary); background: var(--primary-light); color: var(--fg); border-radius: 0 6px 6px 0; }
.content table { border-collapse: collapse; width: 100%; margin: 0 0 18px; font-size: 14px; }
.content th, .content td { padding: 10px 12px; border-bottom: 1px solid var(--border); text-align: left; vertical-align: top; }
.content th { background: var(--surface); font-weight: 600; }

/* ── Cards ────────────────────────────────────────── */
.cards {
  display: grid;
  gap: 16px;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  margin: 24px 0;
}
.card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 18px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: all .15s ease;
}
.card:hover { border-color: var(--primary); box-shadow: var(--shadow-md); text-decoration: none; }
.card .icon {
  width: 36px; height: 36px;
  display: inline-flex; align-items: center; justify-content: center;
  background: var(--primary-light); color: var(--primary);
  border-radius: 8px;
}
.card h3 { margin: 4px 0 0; font-size: 16px; font-weight: 600; color: var(--fg); }
.card p { margin: 0; color: var(--fg-soft); font-size: 14px; }

/* ── Callouts ─────────────────────────────────────── */
.callout {
  margin: 18px 0;
  padding: 14px 16px;
  border: 1px solid var(--border);
  border-left-width: 3px;
  border-radius: 6px;
  background: var(--surface);
  font-size: 14px;
}
.callout strong { color: var(--fg); }
.callout.info    { border-left-color: var(--primary); background: var(--primary-light); }
.callout.warn    { border-left-color: #FFA600; background: #FFF8EC; }
.callout.danger  { border-left-color: #DC2626; background: #FEF2F2; }
.callout.success { border-left-color: #14AA51; background: #ECFDF5; }

/* ── Footer ───────────────────────────────────────── */
.footer {
  background: var(--surface);
  border-top: 1px solid var(--border-light);
  padding: 40px 24px 24px;
  color: var(--fg-soft);
  font-size: 14px;
}
.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 32px;
}
@media (max-width: 720px) { .footer-inner { grid-template-columns: 1fr 1fr; } }
.footer h5 { color: var(--fg); font-size: 13px; font-weight: 600; margin: 0 0 10px; text-transform: uppercase; letter-spacing: .06em; }
.footer ul { list-style: none; padding: 0; margin: 0; }
.footer li { margin: 4px 0; }
.footer a { color: var(--fg-soft); }
.footer a:hover { color: var(--primary); text-decoration: none; }
.footer-bottom {
  max-width: 1200px;
  margin: 32px auto 0;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  font-size: 12px;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

/* ── Mobile nav toggle ───────────────────────────── */
.nav-toggle { display: none; background: none; border: 0; padding: 6px; color: var(--fg); cursor: pointer; }
@media (max-width: 800px) {
  .nav-toggle { display: inline-flex; }
  .nav-links { display: none; width: 100%; flex-direction: column; align-items: stretch; gap: 4px; padding-top: 8px; margin-left: 0; }
  .nav-links.open { display: flex; }
  .nav-links a { padding: 10px 14px; }
  .btn-primary.nav-cta { margin: 8px 0 0; align-self: flex-start; }
}

/* ── Misc ─────────────────────────────────────────── */
.kbd { font-family: var(--font-mono); font-size: 12px; padding: 2px 6px; background: var(--card); border: 1px solid var(--border); border-radius: 4px; box-shadow: 0 1px 0 var(--border); }
.tag-row { display: flex; flex-wrap: wrap; gap: 6px; }
.tag { font-family: var(--font-mono); font-size: 12px; padding: 3px 8px; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-pill); color: var(--fg-soft); }
.tag.primary { background: var(--primary-light); color: var(--primary); border-color: rgba(0,107,255,.2); }

hr { border: 0; border-top: 1px solid var(--border-light); margin: 24px 0; }