:root {
  --paper: #f7f5f0;
  --card: #fffefb;
  --ink: #1c1e22;
  --muted: #5c6470;
  --line: #dcd7cc;
  --accent: #2f5d50;
  --accent-ink: #ffffff;
  --accent-tint: #e6efec;
  --serif: 'Fraunces', Georgia, serif;
  --sans: 'Inter', -apple-system, 'Helvetica Neue', sans-serif;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme='light']) {
    --paper: #14161a;
    --card: #1c1f24;
    --ink: #e8e6e1;
    --muted: #9aa2ad;
    --line: #30343b;
    --accent: #7fb8a6;
    --accent-ink: #10231d;
    --accent-tint: #1f2e29;
  }
}
:root[data-theme='dark'] {
  --paper: #14161a;
  --card: #1c1f24;
  --ink: #e8e6e1;
  --muted: #9aa2ad;
  --line: #30343b;
  --accent: #7fb8a6;
  --accent-ink: #10231d;
  --accent-tint: #1f2e29;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 17px/1.6 var(--sans);
}
a { color: var(--accent); }
main { max-width: 980px; margin: 0 auto; padding: 0 16px 4rem; }

.top {
  max-width: 980px;
  margin: 0 auto;
  padding: 1rem 16px;
  display: flex;
  align-items: center;
  gap: 1rem;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font: 600 1.15rem var(--serif);
  color: var(--ink);
  text-decoration: none;
  margin-right: auto;
}
.gh { font-weight: 500; text-decoration: none; }
.menu { position: relative; }
.menu summary { cursor: pointer; font-weight: 500; color: var(--accent); list-style: none; }
.menu summary::-webkit-details-marker { display: none; }
.menu summary::after { content: ' ▾'; }
.menu ol {
  position: absolute;
  right: 0;
  z-index: 2;
  margin: 0.5rem 0 0;
  padding: 0.5rem 0.75rem 0.5rem 2rem;
  width: min(22rem, calc(100vw - 32px));
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 12px;
  box-shadow: 0 8px 30px rgb(0 0 0 / 0.12);
}
.menu li { margin: 0.35rem 0; }

.hero { padding: 3.5rem 0 2.5rem; }
.eyebrow { color: var(--muted); letter-spacing: 0.04em; text-transform: uppercase; font-size: 0.8rem; margin: 0; }
h1, h2, h3 { font-family: var(--serif); line-height: 1.2; }
.hero h1 { font-size: clamp(2rem, 5vw, 3.2rem); margin: 0.5rem 0 1rem; max-width: 18ch; }
.lede { font-size: 1.15rem; color: var(--muted); max-width: 60ch; }
.cta { display: flex; flex-wrap: wrap; gap: 0.75rem; margin-top: 1.5rem; }
.button {
  display: inline-block;
  padding: 0.7rem 1.2rem;
  border-radius: 999px;
  border: 1px solid var(--accent);
  text-decoration: none;
  font-weight: 600;
}
.button.primary { background: var(--accent); color: var(--accent-ink); }

section { margin: 3rem 0; }
section h2 { font-size: 1.6rem; margin-bottom: 1rem; }
.story-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 1.5rem; }
.story-grid p { margin: 0; }
.feature-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 1rem; }
.feature {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 1.1rem 1.2rem;
}
.feature h3 { margin: 0 0 0.4rem; font-size: 1.1rem; }
.feature p { margin: 0; color: var(--muted); }
.principles ul { padding-left: 1.2rem; max-width: 70ch; }
.principles li { margin: 0.5rem 0; }
.tutorial-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 0.75rem; }
.tutorial-card {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  padding: 0.9rem 1rem;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  color: var(--ink);
  text-decoration: none;
  font-weight: 500;
}
.tutorial-card:hover { border-color: var(--accent); }
.tutorial-card .num {
  flex: none;
  width: 2rem;
  height: 2rem;
  border-radius: 999px;
  background: var(--accent-tint);
  color: var(--accent);
  display: grid;
  place-items: center;
  font-weight: 600;
}
.muted { color: var(--muted); }

.prose { max-width: 72ch; padding-top: 1.5rem; }
.prose h1 { font-size: clamp(1.8rem, 4vw, 2.4rem); }
.prose h2 { font-size: 1.35rem; margin-top: 2rem; }
.prose table { border-collapse: collapse; width: 100%; display: block; overflow-x: auto; margin: 1rem 0; }
.prose th, .prose td { border: 1px solid var(--line); padding: 0.45rem 0.7rem; text-align: left; vertical-align: top; }
.prose th { background: var(--accent-tint); }
.prose pre {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 0.9rem 1rem;
  overflow-x: auto;
  font-size: 0.9rem;
}
.prose code { font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: 0.92em; }
.prose blockquote { margin: 1rem 0; padding: 0.2rem 1rem; border-left: 3px solid var(--accent); color: var(--muted); }
.pager { max-width: 72ch; display: flex; justify-content: space-between; gap: 1rem; margin-top: 3rem; padding-top: 1rem; border-top: 1px solid var(--line); }
.pager a { text-decoration: none; font-weight: 500; }

.foot { border-top: 1px solid var(--line); color: var(--muted); font-size: 0.9rem; }
.foot p { max-width: 980px; margin: 0 auto; padding: 1.5rem 16px; }