:root {
  --bg: #ffffff;
  --fg: #1f2328;
  --muted: #59636e;
  --border: #d1d9e0;
  --sidebar: #f6f8fa;
  --accent: #b8541a;
  --code-bg: #f6f8fa;
  --note-bg: #fff8e6;
  --note-border: #e3b341;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d1117;
    --fg: #e6edf3;
    --muted: #9198a1;
    --border: #30363d;
    --sidebar: #151b23;
    --accent: #f0883e;
    --code-bg: #161b22;
    --note-bg: #2a2214;
    --note-border: #9e6a03;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", sans-serif;
  display: grid;
  grid-template-columns: 260px minmax(0, 1fr);
  min-height: 100vh;
}

nav {
  background: var(--sidebar);
  border-right: 1px solid var(--border);
  padding: 1.5rem 1.25rem;
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
}

nav .brand {
  display: block;
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--fg);
  text-decoration: none;
  margin-bottom: 1.5rem;
}

nav .brand span { color: var(--accent); }

nav h2 {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--muted);
  margin: 1.25rem 0 0.4rem;
}

nav ul { list-style: none; padding: 0; margin: 0; }

nav a {
  display: block;
  padding: 0.2rem 0.5rem;
  border-radius: 6px;
  color: var(--fg);
  text-decoration: none;
}

nav a:hover { background: var(--border); }
nav a[aria-current="page"] { background: var(--accent); color: #fff; }

main {
  padding: 2.5rem 3rem 4rem;
  max-width: 920px;
}

h1 { font-size: 2.1rem; margin-top: 0; line-height: 1.2; }
h2 { margin-top: 2.5rem; padding-bottom: 0.3rem; border-bottom: 1px solid var(--border); }
h3 { margin-top: 1.8rem; }

.lead { font-size: 1.15rem; color: var(--muted); }

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

code, pre { font-family: var(--mono); font-size: 0.88em; }

:not(pre) > code {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 0.05em 0.35em;
}

pre {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1rem 1.1rem;
  overflow-x: auto;
  line-height: 1.45;
}

pre .comment { color: var(--muted); }

table {
  border-collapse: collapse;
  width: 100%;
  margin: 1rem 0;
  font-size: 0.94rem;
}

th, td {
  border: 1px solid var(--border);
  padding: 0.45rem 0.7rem;
  text-align: left;
  vertical-align: top;
}

th { background: var(--sidebar); }
td code { white-space: nowrap; }

.note {
  background: var(--note-bg);
  border-left: 4px solid var(--note-border);
  border-radius: 4px;
  padding: 0.7rem 1rem;
  margin: 1.2rem 0;
}

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 1rem;
  margin: 1.5rem 0;
}

.cards a {
  display: block;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1rem;
  color: var(--fg);
  text-decoration: none;
}

.cards a:hover { border-color: var(--accent); }
.cards strong { display: block; color: var(--accent); margin-bottom: 0.3rem; }

footer {
  margin-top: 4rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.85rem;
}

@media (max-width: 800px) {
  body { display: block; }
  nav { position: static; height: auto; border-right: 0; border-bottom: 1px solid var(--border); }
  main { padding: 1.5rem 1.25rem 3rem; }
}