:root {
  --bg: #fafaf8;
  --card: #ffffff;
  --text: #1f2933;
  --muted: #5b6770;
  --line: #e3e5e2;
  --accent: #1f4e5f;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.65 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
a { color: var(--accent); }
.wrap { max-width: 760px; margin: 0 auto; padding: 0 24px; }
header { border-bottom: 1px solid var(--line); background: var(--card); }
header .wrap { display: flex; justify-content: space-between; align-items: center; padding-top: 18px; padding-bottom: 18px; }
.brand { font-weight: 650; letter-spacing: .01em; text-decoration: none; color: var(--text); }
nav a { margin-left: 20px; text-decoration: none; color: var(--muted); font-size: 15px; }
nav a:hover { color: var(--accent); }
.hero { padding: 72px 0 40px; }
.hero h1 { font-size: clamp(30px, 5vw, 42px); line-height: 1.2; margin: 0 0 16px; }
.hero p { color: var(--muted); font-size: 19px; margin: 0; max-width: 34em; }
section { padding: 28px 0; }
h2 { font-size: 22px; margin: 0 0 12px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 10px; padding: 24px; }
.btn {
  display: inline-block; margin-top: 20px; padding: 12px 22px; border-radius: 8px;
  background: var(--accent); color: #fff; text-decoration: none; font-weight: 600;
}
.btn:hover { opacity: .9; }
dl { margin: 0; }
dt { font-weight: 600; margin-top: 12px; }
dd { margin: 0; color: var(--muted); }
article h2 { margin-top: 36px; }
article ul { padding-left: 22px; }
article li { margin: 4px 0; }
.updated { color: var(--muted); font-size: 15px; }
footer { border-top: 1px solid var(--line); margin-top: 48px; padding: 28px 0 40px; color: var(--muted); font-size: 14px; }
footer a { color: var(--muted); }