:root {
  --bg: #ffffff;
  --bg-alt: #f5f6f8;
  --text: #16181d;
  --muted: #5b6270;
  --accent: #1f4fd8;
  --border: #e1e4ea;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1115;
    --bg-alt: #171a21;
    --text: #eef0f4;
    --muted: #9aa2b1;
    --accent: #7c9bff;
    --border: #272c36;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font: 16px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
}
a { color: var(--accent); }
.wrap { max-width: 960px; margin: 0 auto; padding: 0 16px; }
header.site { border-bottom: 1px solid var(--border); }
header.site .wrap { display: flex; align-items: center; justify-content: space-between; padding-top: 16px; padding-bottom: 16px; flex-wrap: wrap; gap: 8px; }
.brand { font-weight: 700; font-size: 1.1rem; color: var(--text); text-decoration: none; }
nav a { margin-left: 16px; text-decoration: none; color: var(--muted); }
nav a:hover { color: var(--accent); }
.hero { padding-top: 72px; padding-bottom: 56px; }
.hero h1 { font-size: clamp(2rem, 5vw, 3rem); line-height: 1.15; margin: 0 0 16px; }
.hero p { font-size: 1.15rem; color: var(--muted); max-width: 640px; margin: 0 0 24px; }
.btn { display: inline-block; background: var(--accent); color: #fff; padding: 10px 20px; border-radius: 8px; text-decoration: none; font-weight: 600; }
section { padding: 56px 0; }
section.alt { background: var(--bg-alt); }
h2 { margin: 0 0 24px; font-size: 1.6rem; }
.grid { display: grid; gap: 16px; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); }
.card { background: var(--bg); border: 1px solid var(--border); border-radius: 12px; padding: 20px; }
.card h3 { margin: 0 0 8px; font-size: 1.1rem; }
.card p { margin: 0; color: var(--muted); }
dl.details { display: grid; grid-template-columns: max-content 1fr; gap: 8px 24px; margin: 0; }
dl.details dt { font-weight: 600; }
dl.details dd { margin: 0; color: var(--muted); }
@media (max-width: 520px) { dl.details { grid-template-columns: 1fr; gap: 0; } dl.details dd { margin-bottom: 12px; } }
footer { border-top: 1px solid var(--border); padding: 24px 0; color: var(--muted); font-size: 0.9rem; }
footer .wrap { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px; }
.prose { max-width: 720px; padding: 48px 0; }
.prose h1 { margin-top: 0; }