:root {
  --bg: #0a0a0a;
  --surface: #141414;
  --text: #f5f5f5;
  --muted: #9a9a9a;
  --accent: #ff6b1a;
  --border: #232323;
  --max: 720px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "Segoe UI", Roboto, system-ui, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

body {
  padding: 32px 20px 80px;
}

.container {
  max-width: var(--max);
  margin: 0 auto;
}

nav.top {
  max-width: var(--max);
  margin: 0 auto 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}

nav.top a {
  color: var(--muted);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
}

nav.top a:hover { color: var(--accent); }

header.hero {
  text-align: center;
  padding: 48px 0 40px;
}

header.hero h1 {
  font-size: 56px;
  font-weight: 900;
  letter-spacing: -0.02em;
  color: var(--accent);
  margin: 0 0 12px;
}

header.hero p {
  color: var(--muted);
  font-size: 17px;
  margin: 0;
}

.nav-cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  max-width: var(--max);
  margin: 0 auto;
}

@media (min-width: 640px) {
  .nav-cards { grid-template-columns: repeat(3, 1fr); }
}

.nav-cards a {
  display: block;
  padding: 24px 20px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  color: var(--text);
  text-decoration: none;
  transition: border-color 120ms ease, transform 120ms ease;
}

.nav-cards a:hover {
  border-color: var(--accent);
  transform: translateY(-1px);
}

.nav-cards a strong {
  display: block;
  font-size: 17px;
  margin-bottom: 4px;
}

.nav-cards a span {
  color: var(--muted);
  font-size: 13px;
}

article {
  max-width: var(--max);
  margin: 0 auto;
}

article h1 {
  font-size: 32px;
  font-weight: 800;
  letter-spacing: -0.01em;
  margin: 0 0 24px;
}

article h2 {
  font-size: 20px;
  font-weight: 700;
  margin: 40px 0 12px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}

article h2:first-of-type { border-top: none; padding-top: 0; }

article h3 {
  font-size: 16px;
  font-weight: 600;
  margin: 24px 0 8px;
  color: var(--text);
}

article p, article li {
  color: var(--text);
  margin: 8px 0;
}

article a {
  color: var(--accent);
  text-decoration: underline;
}

article ul, article ol {
  padding-left: 24px;
}

article hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 32px 0;
}

article table {
  border-collapse: collapse;
  width: 100%;
  margin: 16px 0;
  font-size: 14px;
}

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

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

article em, article i {
  color: var(--muted);
  font-style: italic;
}

article code {
  background: var(--surface);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 13px;
  font-family: "SF Mono", Menlo, Consolas, monospace;
}

article strong { font-weight: 700; }

footer.page-footer {
  max-width: var(--max);
  margin: 64px auto 0;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 13px;
  text-align: center;
}

footer.page-footer a { color: var(--muted); }