:root {
  --bg: #ffffff; --fg: #14181f; --muted: #5b6472;
  --line: #e3e7ec; --accent: #2563eb; --soft: #f5f7fa;
}
@media (prefers-color-scheme: dark) {
  :root { --bg:#0f1216; --fg:#e8ebef; --muted:#9aa4b2; --line:#242a33; --accent:#6ea0ff; --soft:#161b22; }
}
* { box-sizing: border-box; }
body {
  margin: 0; background: var(--bg); color: var(--fg);
  font: 17px/1.7 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}
.wrap { max-width: 720px; margin: 0 auto; padding: 56px 20px 80px; }
h1 { font-size: clamp(26px, 4vw, 36px); line-height: 1.25; margin: 0 0 14px; letter-spacing: -.02em; }
h2 { font-size: 22px; margin: 34px 0 10px; letter-spacing: -.01em; }
h3 { font-size: 17px; margin: 22px 0 6px; }
p, li { color: var(--muted); }
ul, ol { padding-left: 22px; }
li { margin-bottom: 6px; }
a { color: var(--accent); }
.lede { font-size: 19px; color: var(--fg); }
.card {
  margin: 24px 0; padding: 20px; border: 1px solid var(--line);
  border-radius: 12px; background: var(--soft);
}
.card p:first-child { margin-top: 0; }
.card p:last-child { margin-bottom: 0; }
.cta {
  display: inline-block; margin: 8px 0 4px; padding: 12px 18px;
  border-radius: 10px; background: var(--accent); color: #fff;
  font-weight: 600; text-decoration: none;
}
.nav { display: flex; gap: 14px; flex-wrap: wrap; font-size: 14px; margin-top: 40px; }
.nav a { text-decoration: none; }
footer { margin-top: 48px; padding-top: 20px; border-top: 1px solid var(--line); color: var(--muted); font-size: 14px; }