:root {
  color-scheme: dark;
  --bg: #070707;
  --panel: #111;
  --line: #292929;
  --text: #f7f7f4;
  --muted: #aaa;
}

* { box-sizing: border-box; }
html { background: var(--bg); }
body {
  margin: 0;
  min-height: 100vh;
  background: radial-gradient(circle at 50% -20%, #292929 0, var(--bg) 34rem);
  color: var(--text);
  font: 16px/1.65 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", sans-serif;
}
a { color: inherit; }
.shell { width: min(760px, calc(100% - 40px)); margin: 0 auto; }
header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 28px 0;
  border-bottom: 1px solid var(--line);
}
.brand { display: flex; align-items: center; gap: 11px; text-decoration: none; font-weight: 750; letter-spacing: -.02em; }
.app-icon { width: 38px; height: 38px; border-radius: 9px; display: block; }
nav { display: flex; gap: 18px; }
nav a { color: var(--muted); text-decoration: none; font-size: 14px; }
nav a:hover { color: var(--text); }
main { padding: 72px 0 96px; }
.eyebrow { color: var(--muted); font-size: 13px; font-weight: 650; letter-spacing: .09em; text-transform: uppercase; }
h1 { max-width: 680px; margin: 12px 0 18px; font-size: clamp(42px, 8vw, 68px); line-height: 1.02; letter-spacing: -.055em; }
.lead { max-width: 650px; color: #cacaca; font-size: 19px; line-height: 1.55; }
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin-top: 42px; }
.card { min-height: 176px; padding: 24px; border: 1px solid var(--line); border-radius: 20px; background: linear-gradient(145deg, #161616, #0d0d0d); text-decoration: none; }
.card span { color: var(--muted); font-size: 13px; }
.card h2 { margin: 34px 0 6px; font-size: 20px; letter-spacing: -.025em; }
.card p { margin: 0; color: var(--muted); font-size: 14px; }
.document { padding-top: 52px; }
.document h1 { font-size: clamp(38px, 7vw, 58px); }
.document .meta { color: var(--muted); font-size: 14px; }
.document section { padding: 27px 0; border-top: 1px solid var(--line); }
.document section:first-of-type { margin-top: 42px; }
.document h2 { margin: 0 0 10px; font-size: 21px; letter-spacing: -.025em; }
.document p, .document li { color: #c5c5c5; }
.document ul { padding-left: 22px; }
.callout { padding: 20px; border: 1px solid #3b3b3b; border-radius: 16px; background: var(--panel); }
.button { display: inline-block; margin-top: 10px; padding: 12px 17px; border-radius: 12px; background: var(--text); color: #080808; font-weight: 700; text-decoration: none; }
footer { padding: 28px 0 48px; border-top: 1px solid var(--line); color: var(--muted); font-size: 13px; }

@media (max-width: 650px) {
  header { align-items: flex-start; gap: 20px; }
  nav { gap: 11px; flex-wrap: wrap; justify-content: flex-end; }
  main { padding-top: 48px; }
  .cards { grid-template-columns: 1fr; }
  .card { min-height: 140px; }
  .card h2 { margin-top: 20px; }
}