:root {
  color-scheme: dark;
  --bg: #08192D;
  --bg-elevated: #0D233C;
  --surface: #102B48;
  --surface-soft: #0B2138;
  --text: #F5F7FA;
  --muted: #A8B6C7;
  --subtle: #71849A;
  --accent: #5EA0FF;
  --accent-soft: rgba(94,160,255,.12);
  --border: rgba(255,255,255,.09);
  --warning: #F2A94A;
  --max: 1120px;
  --radius-lg: 28px;
  --radius-md: 18px;
  --shadow: 0 20px 60px rgba(0,0,0,.20);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; background: var(--bg); }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "SF Pro Display", "Helvetica Neue", Arial, sans-serif;
  background:
    radial-gradient(900px 460px at 82% -10%, rgba(94,160,255,.12), transparent 70%),
    var(--bg);
  color: var(--text);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
a { color: inherit; text-underline-offset: .18em; }
a:hover { color: #fff; }

.skip-link {
  position: absolute;
  left: -9999px;
  top: 10px;
  z-index: 100;
  background: #fff;
  color: #000;
  padding: 10px 14px;
  border-radius: 10px;
}
.skip-link:focus { left: 10px; }

.wrap { width: min(calc(100% - 40px), var(--max)); margin: 0 auto; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: saturate(150%) blur(16px);
  -webkit-backdrop-filter: saturate(150%) blur(16px);
  background: rgba(8,25,45,.78);
  border-bottom: 1px solid var(--border);
}
.nav {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.brand {
  font-weight: 760;
  letter-spacing: -.02em;
  text-decoration: none;
  font-size: 1.08rem;
}
.nav-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
  list-style: none;
  padding: 0;
  margin: 0;
  color: var(--muted);
  font-size: .95rem;
}
.nav-links a { text-decoration: none; padding: 10px 0; }
.nav-links a[aria-current="page"] { color: var(--text); }

.hero { padding: 112px 0 76px; }
.eyebrow {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  padding: 6px 12px;
  border: 1px solid rgba(94,160,255,.25);
  background: var(--accent-soft);
  border-radius: 999px;
  color: #BED8FF;
  font-size: .86rem;
  font-weight: 650;
  letter-spacing: .01em;
}
.hero h1 {
  max-width: 850px;
  margin: 24px 0 20px;
  font-size: clamp(3.1rem, 8vw, 6.6rem);
  line-height: .96;
  letter-spacing: -.055em;
  font-weight: 760;
}
.hero .lede {
  max-width: 720px;
  color: var(--muted);
  font-size: clamp(1.16rem, 2.2vw, 1.45rem);
  margin: 0;
}
.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}
.button {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  padding: 0 18px;
  border-radius: 14px;
  border: 1px solid var(--border);
  text-decoration: none;
  font-weight: 660;
}
.button.primary { background: var(--accent); color: #04111F; border-color: transparent; }
.button.secondary { background: rgba(255,255,255,.04); color: var(--text); }

.section { padding: 54px 0; }
.section + .section { border-top: 1px solid rgba(255,255,255,.05); }
.section-title {
  max-width: 760px;
  margin-bottom: 28px;
}
.section-title h2 {
  margin: 0 0 10px;
  font-size: clamp(2rem, 4.5vw, 3.2rem);
  line-height: 1.05;
  letter-spacing: -.035em;
}
.section-title p { margin: 0; color: var(--muted); font-size: 1.08rem; }

.grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}
.card {
  background: linear-gradient(180deg, rgba(255,255,255,.028), rgba(255,255,255,.012));
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
}
.card h3 { margin: 0 0 9px; font-size: 1.2rem; letter-spacing: -.01em; }
.card p { margin: 0; color: var(--muted); }

.notice {
  display: grid;
  gap: 8px;
  padding: 28px;
  border-radius: var(--radius-lg);
  border: 1px solid rgba(242,169,74,.28);
  background: rgba(242,169,74,.06);
}
.notice strong { color: #FFD59C; }
.notice p { margin: 0; color: #D6C2A7; }

.page-hero {
  padding: 82px 0 38px;
}
.page-hero h1 {
  margin: 0 0 14px;
  font-size: clamp(2.55rem, 6vw, 4.4rem);
  line-height: 1;
  letter-spacing: -.045em;
}
.page-hero p {
  max-width: 720px;
  margin: 0;
  color: var(--muted);
  font-size: 1.15rem;
}

.prose {
  max-width: 820px;
  padding-bottom: 76px;
}
.prose h2 {
  margin: 42px 0 10px;
  font-size: 1.45rem;
  letter-spacing: -.02em;
}
.prose p, .prose li { color: #C9D3DE; }
.prose ul { padding-left: 1.25rem; }
.prose code {
  background: rgba(255,255,255,.06);
  border: 1px solid var(--border);
  padding: .08em .38em;
  border-radius: 6px;
}
.meta-note {
  display: inline-block;
  margin-top: 8px;
  color: var(--subtle);
  font-size: .92rem;
}

.definition-grid {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 10px 20px;
  padding: 22px 0;
}
.definition-grid dt { color: var(--muted); }
.definition-grid dd { margin: 0; color: var(--text); }

.site-footer {
  border-top: 1px solid var(--border);
  padding: 36px 0 44px;
  color: var(--muted);
  font-size: .92rem;
}
.footer-row {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
}
.footer-links { display: flex; flex-wrap: wrap; gap: 14px 18px; }
.footer-links a { text-decoration: none; }

@media (max-width: 760px) {
  .wrap { width: min(calc(100% - 28px), var(--max)); }
  .site-header { position: static; }
  .nav { align-items: flex-start; flex-direction: column; padding: 18px 0; gap: 6px; }
  .nav-links { gap: 0 18px; }
  .hero { padding: 76px 0 52px; }
  .hero h1 { font-size: clamp(3.05rem, 17vw, 4.8rem); }
  .grid { grid-template-columns: 1fr; }
  .card, .notice { padding: 22px; }
  .definition-grid { grid-template-columns: 1fr; gap: 2px; }
  .definition-grid dd { margin-bottom: 12px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}