:root {
  --teal: #0e9f8e;
  --teal-dark: #0a6359;
  --ink: #16302d;
  --muted: #5a716d;
  --bg: #ffffff;
  --card: #f3fbf9;
  --line: #d6ece7;
}

@media (prefers-color-scheme: dark) {
  :root {
    --ink: #e6f4f1;
    --muted: #9bb7b2;
    --bg: #0d1b19;
    --card: #12272a;
    --line: #1f3d3a;
    --teal: #2fcfac;
    --teal-dark: #66e4c4;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

a {
  color: var(--teal-dark);
}

.top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 960px;
  margin: 0 auto;
  padding: 20px 24px;
}

.brand {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--teal);
  text-decoration: none;
}

.top nav a {
  color: var(--muted);
  text-decoration: none;
}

main {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 24px 48px;
}

.hero {
  padding: 48px 0 32px;
}

.hero h1 {
  margin: 0 0 12px;
  font-size: clamp(2rem, 6vw, 3.2rem);
  line-height: 1.1;
}

.lead {
  max-width: 640px;
  margin: 0;
  font-size: 1.15rem;
  color: var(--muted);
}

.grid {
  display: grid;
  gap: 16px;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  margin: 24px 0 40px;
}

.grid article {
  padding: 20px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 12px;
}

.grid h2,
.note h2 {
  margin: 0 0 8px;
  font-size: 1.1rem;
}

.grid p {
  margin: 0;
  color: var(--muted);
}

.note {
  max-width: 680px;
}

.doc {
  max-width: 720px;
}

.doc h1 {
  margin: 24px 0 4px;
}

.doc h2 {
  margin: 32px 0 8px;
  font-size: 1.15rem;
}

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

code {
  padding: 1px 5px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 4px;
  font-size: 0.9em;
  word-break: break-all;
}

footer {
  max-width: 960px;
  margin: 0 auto;
  padding: 24px;
  color: var(--muted);
  border-top: 1px solid var(--line);
  font-size: 0.9rem;
}