:root { --ink: #1d2733; --muted: #5b6876; --line: #e3e8ee; --accent: #1f6fb2; --bg: #fbfcfd; }
* { box-sizing: border-box; }
body { margin: 0; font: 16px/1.65 -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif; color: var(--ink); background: var(--bg); }
.wrap { max-width: 960px; margin: 0 auto; padding: 0 20px; }
a { color: var(--accent); text-decoration: none; }
.top { border-bottom: 1px solid var(--line); background: #fff; }
.top .wrap { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { font-weight: 700; font-size: 18px; color: var(--ink); letter-spacing: .2px; }
nav a { margin-left: 22px; color: var(--muted); font-size: 15px; }
nav a:hover { color: var(--ink); }
.hero { padding: 72px 0 48px; }
.hero h1 { font-size: 36px; line-height: 1.25; margin: 0 0 16px; max-width: 720px; }
.hero p { font-size: 18px; color: var(--muted); max-width: 640px; margin: 0; }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 20px; padding-bottom: 40px; }
.grid article { background: #fff; border: 1px solid var(--line); border-radius: 8px; padding: 22px; }
.grid h2 { font-size: 18px; margin: 0 0 8px; }
.grid p { margin: 0; color: var(--muted); font-size: 15px; }
.prose { padding: 8px 20px 32px; }
.prose h2 { font-size: 22px; margin: 24px 0 10px; }
.prose p { color: var(--muted); max-width: 720px; }
.notes { padding-left: 18px; color: var(--muted); max-width: 720px; }
.notes li { margin-bottom: 10px; }
.notes strong { color: var(--ink); }
.foot { border-top: 1px solid var(--line); padding-top: 18px; padding-bottom: 32px; color: var(--muted); font-size: 14px; }
@media (max-width: 600px) { .hero h1 { font-size: 28px; } nav a { margin-left: 14px; } }