:root { --accent: #4338ca; --text: #1f2330; --muted: #5b6070; --bg: #fff; --line: #e4e6ee; }
@media (prefers-color-scheme: dark) {
  :root { --accent: #a5b4fc; --text: #e8e9f0; --muted: #a3a8b8; --bg: #14161d; --line: #2b2f3b; }
}
* { box-sizing: border-box; }
body { margin: 0; font: 17px/1.6 system-ui, sans-serif; color: var(--text); background: var(--bg); }
header, main, footer { max-width: 760px; margin: 0 auto; padding: 0 20px; }
header { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; justify-content: space-between;
  padding-top: 20px; padding-bottom: 12px; border-bottom: 1px solid var(--line); }
.brand { display: flex; gap: 10px; align-items: center; font-weight: 700; font-size: 20px;
  color: var(--text); text-decoration: none; }
nav { font-size: 15px; }
nav a { margin-right: 8px; }
a { color: var(--accent); }
h1 { font-size: 34px; margin: 28px 0 8px; }
h2 { font-size: 22px; margin-top: 32px; }
.lead { font-size: 19px; }
.small { font-size: 15px; color: var(--muted); }
.button { display: inline-block; padding: 10px 20px; border-radius: 8px; background: var(--accent);
  color: var(--bg); font-weight: 600; text-decoration: none; }
code { font-size: 15px; }
footer { margin-top: 40px; padding-top: 16px; padding-bottom: 32px; border-top: 1px solid var(--line);
  font-size: 14px; color: var(--muted); }