:root {
  --bg: #0d1117;
  --surface: #161b22;
  --border: #30363d;
  --text: #e6edf3;
  --muted: #8b949e;
  --accent: #58a6ff;
  --accent-hover: #79c0ff;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas,
    "Liberation Mono", monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial,
    sans-serif;
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--sans);
  line-height: 1.6;
  color: var(--text);
  background-color: var(--bg);
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}
.container {
  width: 100%;
  max-width: 820px;
  margin: 0 auto;
  padding: 0 20px;
}
header {
  padding: 24px 0 14px;
  border-bottom: 1px solid var(--border);
}
header h1 {
  margin: 0;
  font-size: 1.4rem;
  letter-spacing: -0.02em;
}
header h1 a {
  color: var(--accent);
  text-decoration: none;
}
header h1 a:hover { text-decoration: underline; }
main { flex: 1 0 auto; padding: 28px 0; }
article {
  font-size: 1rem;
  overflow-wrap: break-word;
}
article h1, article h2, article h3, article h4 {
  letter-spacing: -0.01em;
  line-height: 1.25;
  margin-top: 1.6em;
  margin-bottom: 0.6em;
}
article h1 { font-size: 1.7rem; margin-top: 0; }
article h2 { font-size: 1.35rem; border-bottom: 1px solid var(--border); padding-bottom: 0.3em; }
article h3 { font-size: 1.12rem; }
article h4 { font-size: 1rem; color: var(--accent-hover); }
article p { margin: 0.8em 0; }
article a { color: var(--accent); text-decoration: none; }
article a:hover { text-decoration: underline; }
article ul, article ol { padding-left: 1.6em; }
article li { margin: 0.25em 0; }
article blockquote {
  margin: 0.9em 0;
  padding: 0.4em 1em;
  border-left: 3px solid var(--border);
  color: var(--muted);
}
article blockquote p { margin: 0.4em 0; }
article code {
  font-family: var(--mono);
  background-color: var(--surface);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 0.9em;
}
article pre {
  font-family: var(--mono);
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 14px 16px;
  margin: 12px 0;
  overflow-x: auto;
  line-height: 1.5;
  font-size: 0.88rem;
}
article pre code {
  background: none; border: none; padding: 0; font-size: inherit;
}
article table {
  border-collapse: collapse;
  margin: 1em 0;
  display: block;
  overflow-x: auto;
}
article table th, article table td {
  border: 1px solid var(--border);
  padding: 6px 12px;
  text-align: left;
}
article table th { background-color: var(--surface); }
article hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 1.6em 0;
}
article img { max-width: 100%; }
.back { margin-top: 0; color: var(--muted); font-size: 0.92rem; }
.back a { color: var(--accent); }
footer {
  flex-shrink: 0;
  padding: 18px 0;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.9rem;
}
footer a { color: var(--muted); text-decoration: none; }
footer a:hover { color: var(--accent); }