:root {
  --fg: #1a1a1a;
  --muted: #6b7280;
  --link: #2563eb;
  --line: #e5e7eb;
  --bg: #ffffff;
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--fg);
  background: var(--bg);
  line-height: 1.65;
  font-size: 16px;
}
.wrap { max-width: 680px; margin: 0 auto; padding: 40px 20px 80px; }
header { margin-bottom: 28px; }
h1 { font-size: 26px; margin: 0 0 6px; }
h2 { font-size: 19px; margin: 32px 0 8px; }
h3 { font-size: 16px; margin: 22px 0 4px; }
p, li { color: var(--fg); }
.muted { color: var(--muted); font-size: 14px; }
a { color: var(--link); text-decoration: none; }
a:hover { text-decoration: underline; }
hr { border: 0; border-top: 1px solid var(--line); margin: 40px 0; }
.nav { margin-top: 20px; display: flex; gap: 12px; flex-wrap: wrap; }
.btn {
  display: inline-block; padding: 12px 18px; border: 1px solid var(--line);
  border-radius: 10px; color: var(--fg); font-weight: 500;
}
.btn:hover { border-color: var(--link); text-decoration: none; }
.lang-label { color: var(--muted); font-size: 13px; text-transform: uppercase; letter-spacing: 0.04em; margin-top: 8px; }
footer { margin-top: 48px; color: var(--muted); font-size: 13px; }