:root {
  color-scheme: light dark;
  --fg: #111;
  --bg: #fafafa;
  --panel: #fff;
  --muted: #555;
  --border: rgba(0, 0, 0, 0.08);
  --accent: #2f80ed;
  --accent-fg: #fff;
}

@media (prefers-color-scheme: dark) {
  :root {
    --fg: #f5f5f5;
    --bg: #0a0a0a;
    --panel: #141414;
    --muted: #a0a0a0;
    --border: rgba(255, 255, 255, 0.08);
    --accent: #6ea8ff;
    --accent-fg: #061226;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  color: var(--fg);
  background: var(--bg);
  line-height: 1.55;
}

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

a:hover {
  text-decoration: underline;
}

code {
  background: rgba(127, 127, 127, 0.18);
  padding: 0.1rem 0.4rem;
  border-radius: 0.3rem;
  font-size: 0.9em;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
}

/* ── Nav ──────────────────────────────────────────────────────────── */

.nav {
  position: sticky;
  top: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  padding: 1rem 2rem;
  background: color-mix(in srgb, var(--bg) 90%, transparent);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  z-index: 10;
}

.brand {
  font-weight: 700;
  color: var(--fg);
  letter-spacing: -0.01em;
}

.brand:hover {
  text-decoration: none;
  opacity: 0.85;
}

.nav nav {
  display: flex;
  gap: 1.5rem;
}

.nav nav a {
  color: var(--muted);
  font-size: 0.95rem;
  transition: color 0.15s;
}

.nav nav a:hover,
.nav nav a[aria-current="page"] {
  color: var(--fg);
  text-decoration: none;
}

.nav nav a[aria-current="page"] {
  font-weight: 600;
}

/* ── Layout ───────────────────────────────────────────────────────── */

main {
  max-width: 64rem;
  margin: 0 auto;
  padding: 3rem 2rem 6rem;
}

footer {
  border-top: 1px solid var(--border);
  padding: 2rem;
  text-align: center;
  color: var(--muted);
  font-size: 0.9rem;
}

/* ── Hero ─────────────────────────────────────────────────────────── */

.hero {
  padding: 3rem 0 4rem;
  max-width: 42rem;
}

.badge {
  display: inline-block;
  font-size: 0.8rem;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  padding: 0.25rem 0.6rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--muted);
  margin-bottom: 1.5rem;
}

h1 {
  margin: 0 0 1rem;
  font-size: clamp(2.25rem, 5vw, 3.25rem);
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.lede {
  font-size: 1.15rem;
  color: var(--muted);
  margin: 0 0 2rem;
}

/* ── CTAs ─────────────────────────────────────────────────────────── */

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.cta {
  display: inline-block;
  padding: 0.75rem 1.25rem;
  border-radius: 0.6rem;
  font-weight: 600;
  font-size: 0.95rem;
  transition:
    transform 0.1s,
    box-shadow 0.15s,
    background 0.15s;
}

.cta:hover {
  text-decoration: none;
  transform: translateY(-1px);
}

.cta.primary {
  background: var(--accent);
  color: var(--accent-fg);
}

.cta.primary:hover {
  box-shadow: 0 6px 24px -8px var(--accent);
}

.cta.secondary {
  background: transparent;
  color: var(--fg);
  border: 1px solid var(--border);
}

.cta.secondary:hover {
  background: var(--panel);
}

/* ── Card grid (hub) ──────────────────────────────────────────────── */

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(16rem, 1fr));
  gap: 1rem;
  margin: 3rem 0;
}

.card {
  position: relative;
  display: block;
  padding: 1.5rem;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 0.9rem;
  color: var(--fg);
  transition:
    border-color 0.15s,
    transform 0.1s;
}

.card:hover {
  text-decoration: none;
  border-color: var(--accent);
  transform: translateY(-2px);
}

.card h2 {
  margin: 0 0 0.4rem;
  font-size: 1.25rem;
  letter-spacing: -0.01em;
}

.card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.card .arrow {
  position: absolute;
  top: 1.5rem;
  right: 1.5rem;
  color: var(--muted);
  transition: transform 0.15s;
}

.card:hover .arrow {
  color: var(--accent);
  transform: translateX(4px);
}

/* ── Feature row (subpages) ───────────────────────────────────────── */

.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr));
  gap: 1.5rem;
  margin: 3rem 0;
}

.feature h3 {
  margin: 0 0 0.5rem;
  font-size: 1.05rem;
}

.feature p {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

/* ── Meta blocks ──────────────────────────────────────────────────── */

.meta {
  margin: 3rem 0 0;
  padding: 1.5rem;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 0.9rem;
}

.meta h3 {
  margin: 0 0 0.75rem;
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: var(--muted);
}

.meta ol {
  margin: 0;
  padding-left: 1.25rem;
}

.meta ol li {
  margin-bottom: 0.6rem;
  color: var(--muted);
}

.meta ol li:last-child {
  margin-bottom: 0;
}

.meta ol li code,
.meta p code {
  color: var(--fg);
}

.back-link {
  margin-top: 3rem;
  color: var(--muted);
}