:root {
  --bg: #f2f2f7;
  --card: #ffffff;
  --text: #1c1c1e;
  --text-secondary: #3a3a3c;
  --muted: #6c6c70;
  --line: #e5e5ea;
  --box: #f2f2f7;
  --accent: #007aff;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #000000;
    --card: #1c1c1e;
    --text: #f2f2f7;
    --text-secondary: #d1d1d6;
    --muted: #8e8e93;
    --line: #38383a;
    --box: #2c2c2e;
    --accent: #0a84ff;
  }
}

*, *::before, *::after { box-sizing: border-box; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  font-size: 16px;
  line-height: 1.7;
  color: var(--text);
  background-color: var(--bg);
  margin: 0;
  padding: 24px 16px 64px;
}

.container {
  max-width: 800px;
  margin: 0 auto;
  background: var(--card);
  border-radius: 16px;
  padding: 40px 48px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 8px;
}

.lang {
  font-size: 14px;
  color: var(--muted);
  white-space: nowrap;
}

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

h1 {
  font-size: 28px;
  font-weight: 700;
  margin: 0 0 8px;
  color: var(--text);
}

.subtitle {
  font-size: 14px;
  color: var(--muted);
  margin: 0 0 40px;
}

h2 {
  font-size: 20px;
  font-weight: 600;
  margin: 40px 0 12px;
  color: var(--text);
  border-bottom: 1px solid var(--line);
  padding-bottom: 8px;
}

h3 { font-size: 17px; font-weight: 600; margin: 24px 0 8px; color: var(--text); }

p { margin: 0 0 16px; color: var(--text-secondary); }

ul { margin: 0 0 16px; padding-left: 24px; color: var(--text-secondary); }
li { margin-bottom: 8px; }

.highlight-box {
  background: var(--box);
  border-radius: 10px;
  padding: 16px 20px;
  margin: 16px 0;
}
.highlight-box p { margin: 0; }

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.9em;
  background: var(--box);
  padding: 1px 5px;
  border-radius: 5px;
}

.footer {
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--line);
  font-size: 14px;
  color: var(--muted);
}

@media (max-width: 600px) {
  .container { padding: 24px 20px; border-radius: 12px; }
  h1 { font-size: 22px; }
  h2 { font-size: 18px; }
}