:root {
  --bg: #f5f6f8;
  --surface: #ffffff;
  --text: #10131a;
  --muted: #5b6472;
  --faint: #8892a0;
  --line: #e2e6ec;
  --brand1: #2563eb;
  --brand2: #1e40af;
  --accent: #1d4ed8;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); }

.wrap { max-width: 760px; margin: 0 auto; padding: 0 24px; }

header.site {
  background: linear-gradient(135deg, var(--brand1), var(--brand2));
  color: #fff;
  padding: 72px 0 64px;
}
header.site .wrap { display: block; }
.brand {
  font-size: 34px;
  font-weight: 700;
  letter-spacing: -0.5px;
  margin: 0 0 10px;
}
.tagline { margin: 0; font-size: 19px; opacity: 0.92; }

nav.site {
  background: var(--surface);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
}
nav.site .wrap { display: flex; gap: 24px; padding-top: 14px; padding-bottom: 14px; }
nav.site a { text-decoration: none; font-weight: 600; font-size: 15px; }

main { padding: 48px 0 72px; }

h2 {
  font-size: 22px;
  margin: 40px 0 12px;
  letter-spacing: -0.2px;
}
h2:first-child { margin-top: 0; }
h3 { font-size: 17px; margin: 26px 0 8px; }

p { color: var(--muted); }
li { color: var(--muted); margin-bottom: 6px; }

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 24px 26px;
  margin-bottom: 20px;
}
.card h3 { margin-top: 0; color: var(--text); }
.card p:last-child { margin-bottom: 0; }

.grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
@media (max-width: 620px) { .grid { grid-template-columns: 1fr; } }

.note {
  border-left: 3px solid var(--accent);
  padding: 4px 0 4px 16px;
  margin: 20px 0;
}

footer.site {
  border-top: 1px solid var(--line);
  padding: 28px 0 48px;
  color: var(--faint);
  font-size: 14px;
}
footer.site a { color: var(--faint); }

.updated { color: var(--faint); font-size: 14px; }