:root {
  --bg: #f7f8fb;
  --card: #ffffff;
  --text: #1a1d29;
  --muted: #6b7280;
  --accent: #2563eb;
  --border: #e5e7eb;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  line-height: 1.6;
}
.container {
  max-width: 760px;
  margin: 0 auto;
  padding: 32px 20px 80px;
}
header { margin-bottom: 32px; }
h1 { font-size: 28px; margin: 0 0 4px; }
.subtitle { color: var(--muted); margin: 0; }
.nav-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-bottom: 40px;
}
@media (max-width: 600px) { .nav-grid { grid-template-columns: 1fr; } }
.card {
  display: block;
  padding: 18px 20px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  text-decoration: none;
  color: inherit;
  transition: border-color .2s, transform .1s;
}
.card:hover { border-color: var(--accent); }
.card:active { transform: scale(.98); }
.card h2 { font-size: 16px; margin: 0 0 4px; }
.card p { font-size: 13px; color: var(--muted); margin: 0; }

article { background: var(--card); padding: 28px 32px; border-radius: 14px; border: 1px solid var(--border); }
article h1 { font-size: 24px; }
article h2 { font-size: 18px; margin-top: 28px; }
article h3 { font-size: 15px; margin-top: 20px; color: var(--muted); }
article p, article li { font-size: 15px; }
article a { color: var(--accent); }
article ul { padding-left: 22px; }
article table { width: 100%; border-collapse: collapse; font-size: 14px; margin: 12px 0; }
article th, article td { padding: 8px 10px; border: 1px solid var(--border); text-align: left; vertical-align: top; }
article th { background: var(--bg); font-weight: 600; }
.lang-switch { font-size: 13px; color: var(--muted); margin-bottom: 12px; }
.lang-switch a { color: var(--accent); text-decoration: none; }
.back { display: inline-block; margin-bottom: 18px; color: var(--accent); text-decoration: none; font-size: 14px; }
.back::before { content: "← "; }
footer { margin-top: 40px; color: var(--muted); font-size: 13px; text-align: center; }
footer a { color: var(--accent); }
.updated { color: var(--muted); font-size: 13px; margin-top: -6px; }