:root {
  color-scheme: light dark;
  --ink: #152033;
  --muted: #5f6b7d;
  --line: #dfe5ee;
  --panel: #ffffff;
  --page: #f5f7fb;
  --brand: #315efb;
  --brand-dark: #2447c7;
  --accent: #13c78b;
  --warn-bg: #fff7dc;
  --warn-ink: #6b5100;
  --radius: 18px;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--ink);
  background: var(--page);
  font-size: 17px;
  line-height: 1.65;
}

a { color: var(--brand-dark); }
a:hover { color: var(--brand); }

.shell {
  width: min(1080px, calc(100% - 32px));
  margin: 0 auto;
}

header {
  position: sticky;
  top: 0;
  z-index: 10;
  border-bottom: 1px solid color-mix(in srgb, var(--line) 85%, transparent);
  background: color-mix(in srgb, var(--page) 91%, transparent);
  backdrop-filter: blur(18px);
}

.nav {
  min-height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  text-decoration: none;
  font-weight: 760;
  letter-spacing: -0.02em;
}

.mark {
  width: 34px;
  height: 34px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--brand) 0 62%, var(--accent) 62% 100%);
  box-shadow: 0 8px 20px color-mix(in srgb, var(--brand) 25%, transparent);
  transform: rotate(45deg) scale(.72);
}

nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  margin: 0;
  padding: 0;
  list-style: none;
}

nav a {
  color: var(--muted);
  text-decoration: none;
  font-size: 15px;
}

nav a[aria-current="page"] { color: var(--ink); font-weight: 700; }

main { padding: 64px 0 88px; }

.hero {
  padding: clamp(42px, 8vw, 88px) 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(260px, .7fr);
  gap: 54px;
  align-items: center;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--brand-dark);
  text-transform: uppercase;
  letter-spacing: .12em;
  font-size: 13px;
  font-weight: 800;
}

h1, h2, h3 {
  line-height: 1.2;
  letter-spacing: -0.03em;
  text-wrap: balance;
}

h1 { margin: 0 0 20px; font-size: clamp(42px, 7vw, 72px); }
h2 { margin: 48px 0 14px; font-size: clamp(27px, 4vw, 38px); }
h3 { margin: 30px 0 8px; font-size: 22px; }

.lead { color: var(--muted); font-size: clamp(19px, 2.3vw, 24px); max-width: 720px; }
.meta { color: var(--muted); font-size: 15px; }

.hero-card, .card, article {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  box-shadow: 0 20px 55px rgba(29, 43, 71, .07);
}

.hero-card { padding: 30px; }
article { padding: clamp(24px, 5vw, 60px); }

.grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.card { padding: 26px; }
.card h2, .card h3 { margin-top: 0; }

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 20px;
  border-radius: 999px;
  background: var(--brand);
  color: white;
  text-decoration: none;
  font-weight: 720;
}

.button:hover { color: white; background: var(--brand-dark); }

.notice {
  margin: 24px 0;
  padding: 18px 20px;
  border-left: 4px solid #d4a000;
  border-radius: 8px;
  color: var(--warn-ink);
  background: var(--warn-bg);
}

table {
  width: 100%;
  border-collapse: collapse;
  margin: 18px 0 28px;
  font-size: 15px;
}

th, td {
  padding: 12px;
  border: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

th { background: color-mix(in srgb, var(--page) 75%, var(--panel)); }

code {
  padding: 2px 6px;
  border-radius: 6px;
  background: color-mix(in srgb, var(--page) 82%, var(--ink));
  font-size: .9em;
}

footer {
  padding: 32px 0 48px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 14px;
}

.footer-row {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
}

.footer-row p { margin: 0; }

@media (max-width: 760px) {
  .nav { align-items: flex-start; padding: 16px 0; flex-direction: column; gap: 10px; }
  header { position: static; }
  .hero { grid-template-columns: 1fr; gap: 28px; }
  .grid { grid-template-columns: 1fr; }
  main { padding-top: 32px; }
  article { border-radius: 14px; }
  table { display: block; overflow-x: auto; }
}

@media (prefers-color-scheme: dark) {
  :root {
    --ink: #edf2ff;
    --muted: #abb6ca;
    --line: #33405a;
    --panel: #151d2d;
    --page: #0e1522;
    --brand: #6e8dff;
    --brand-dark: #9bb0ff;
    --accent: #31dfa7;
    --warn-bg: #3c3212;
    --warn-ink: #ffe89a;
  }
}