:root {
  --bg: #ffffff;
  --fg: #1a1a1a;
  --muted: #5a5a5a;
  --accent: #2563eb;
  --border: #e5e5e5;
  --card: #f7f8fa;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #121316;
    --fg: #e8e8ea;
    --muted: #a0a0a8;
    --accent: #7aa2f7;
    --border: #2a2c31;
    --card: #1a1c20;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  line-height: 1.65;
  font-size: 17px;
  -webkit-text-size-adjust: 100%;
}

.wrap {
  max-width: 780px;
  margin: 0 auto;
  padding: 32px 20px 80px;
}

header {
  border-bottom: 1px solid var(--border);
  padding-bottom: 20px;
  margin-bottom: 32px;
}

.brand {
  font-weight: 700;
  font-size: 20px;
  letter-spacing: -0.01em;
  text-decoration: none;
  color: var(--fg);
}

nav {
  margin-top: 12px;
  font-size: 15px;
}

nav a {
  color: var(--accent);
  text-decoration: none;
  margin-right: 16px;
}

nav a:hover { text-decoration: underline; }

h1 {
  font-size: 30px;
  line-height: 1.25;
  letter-spacing: -0.02em;
  margin: 0 0 8px;
}

h2 {
  font-size: 21px;
  margin: 40px 0 12px;
  letter-spacing: -0.01em;
}

h3 {
  font-size: 17px;
  margin: 24px 0 8px;
}

.meta {
  color: var(--muted);
  font-size: 15px;
  margin: 0 0 8px;
}

.lang-switch {
  display: inline-block;
  margin: 24px 0 0;
  padding: 10px 16px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 15px;
}

.lang-switch a { color: var(--accent); text-decoration: none; font-weight: 600; }

table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0;
  font-size: 15px;
  display: block;
  overflow-x: auto;
}

th, td {
  border: 1px solid var(--border);
  padding: 10px 12px;
  text-align: left;
  vertical-align: top;
}

th { background: var(--card); font-weight: 600; }

ul, ol { padding-left: 24px; }
li { margin: 6px 0; }

a { color: var(--accent); }

code {
  background: var(--card);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 90%;
}

hr {
  border: 0;
  border-top: 1px solid var(--border);
  margin: 56px 0;
}

footer {
  margin-top: 56px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 14px;
}