:root {
  --bg: #f5f6f8;
  --card: #fff;
  --border: #e8eaed;
  --text: #374151;
  --title: #111827;
  --muted: #6b7280;
  --link: #3730a3;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
}
header {
  background: #fff;
  border-bottom: 1px solid #e5e7eb;
  padding: 14px 16px;
}
header a { color: var(--title); text-decoration: none; font-weight: 800; }
nav { display: flex; flex-wrap: wrap; gap: 10px 16px; margin-top: 8px; }
nav a { color: var(--link); font-size: 14px; }
main { max-width: 720px; margin: 0 auto; padding: 20px 16px 48px; }
h1 { font-size: 22px; color: var(--title); margin: 0 0 16px; }
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 16px;
}
p { margin: 0 0 12px; font-size: 15px; }
p:last-child { margin-bottom: 0; }
ul, ol { margin: 0 0 12px; padding-left: 18px; }
li { margin-bottom: 10px; }
.muted { color: var(--muted); font-size: 14px; }
footer { margin-top: 24px; font-size: 13px; color: var(--muted); }
footer a { color: var(--link); }