:root {
  --bg: #fbfaf7;
  --surface: #ffffff;
  --ink: #16181d;
  --muted: #5b6070;
  --line: #e6e3dc;
  --accent: #0f7a5c;
  --accent-ink: #ffffff;
  --accent-soft: #e3f2ec;
  --max: 1040px;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111317;
    --surface: #181b21;
    --ink: #eef0f3;
    --muted: #a3a9b6;
    --line: #2a2f38;
    --accent: #3cc497;
    --accent-ink: #0b1712;
    --accent-soft: #16302a;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 17px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}
a { color: var(--accent); }
.wrap { max-width: var(--max); margin: 0 auto; padding: 0 20px; }
header.top { border-bottom: 1px solid var(--line); }
header.top .wrap { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { font-weight: 700; font-size: 20px; letter-spacing: -0.02em; color: var(--ink); text-decoration: none; }
.brand span { color: var(--accent); }
nav.top a { color: var(--muted); text-decoration: none; margin-left: 20px; font-size: 15px; }
nav.top a:hover { color: var(--ink); }
.hero { padding: 72px 0 56px; }
.hero h1 { font-size: clamp(32px, 5vw, 52px); line-height: 1.1; letter-spacing: -0.03em; margin: 0 0 20px; max-width: 760px; }
.hero p { font-size: 19px; color: var(--muted); max-width: 640px; margin: 0 0 28px; }
.btn {
  display: inline-block; background: var(--accent); color: var(--accent-ink);
  padding: 13px 22px; border-radius: 10px; font-weight: 600; text-decoration: none;
}
.btn.ghost { background: transparent; color: var(--ink); border: 1px solid var(--line); margin-left: 8px; }
.tag { display: inline-block; background: var(--accent-soft); color: var(--accent); font-size: 14px; font-weight: 600; padding: 4px 10px; border-radius: 999px; margin-bottom: 18px; }
section { padding: 48px 0; border-top: 1px solid var(--line); }
section h2 { font-size: 28px; letter-spacing: -0.02em; margin: 0 0 8px; }
section > .wrap > p.lead { color: var(--muted); margin: 0 0 28px; max-width: 640px; }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 16px; }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: 14px; padding: 22px; }
.card h3 { margin: 0 0 6px; font-size: 18px; }
.card p { margin: 0; color: var(--muted); font-size: 16px; }
ol.steps { padding-left: 22px; margin: 0; max-width: 680px; }
ol.steps li { margin-bottom: 12px; }
footer { border-top: 1px solid var(--line); padding: 32px 0 48px; color: var(--muted); font-size: 14px; }
footer .wrap { display: flex; flex-wrap: wrap; gap: 12px 28px; justify-content: space-between; }
footer a { color: var(--muted); }
.doc { padding: 48px 0 64px; }
.doc .wrap { max-width: 760px; }
.doc h1 { font-size: 34px; letter-spacing: -0.02em; margin: 0 0 6px; }
.doc .meta { color: var(--muted); margin: 0 0 32px; }
.doc h2 { font-size: 21px; margin: 32px 0 8px; }
.doc li { margin-bottom: 6px; }
@media (max-width: 560px) {
  nav.top a:not(.keep) { display: none; }
  .btn.ghost { margin: 10px 0 0; }
}