:root {
  --bg: #f7f8fa;
  --surface: #ffffff;
  --text: #1c2430;
  --muted: #5a6573;
  --line: #e2e6eb;
  --accent: #6a3fc1;
  --accent-ink: #ffffff;
  --note: #fff6e0;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #12161c;
    --surface: #1a2029;
    --text: #e6e9ee;
    --muted: #a3acb8;
    --line: #2b3340;
    --accent: #b39af5;
    --accent-ink: #160d2b;
    --note: #2a2618;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.65 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
a { color: var(--accent); }
.wrap { max-width: 760px; margin: 0 auto; padding: 0 16px; }
header.site { background: var(--surface); border-bottom: 1px solid var(--line); }
header.site .wrap { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 8px 20px; padding-top: 14px; padding-bottom: 14px; }
.logo { font-weight: 800; font-size: 20px; color: var(--text); text-decoration: none; letter-spacing: -0.3px; }
.logo span { color: var(--accent); }
nav.main { display: flex; flex-wrap: wrap; gap: 4px 16px; font-size: 15px; }
nav.main a { color: var(--muted); text-decoration: none; }
nav.main a:hover, nav.main a[aria-current="page"] { color: var(--text); }
main { padding: 32px 0 48px; }
h1 { font-size: 32px; line-height: 1.2; margin: 0 0 16px; letter-spacing: -0.5px; }
h2 { font-size: 23px; line-height: 1.3; margin: 36px 0 10px; }
h3 { font-size: 19px; margin: 24px 0 8px; }
.lead { font-size: 19px; color: var(--muted); }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: 10px; padding: 18px 20px; margin: 20px 0; }
.note { background: var(--note); border-radius: 10px; padding: 14px 18px; margin: 20px 0; font-size: 16px; }
.cta { display: inline-block; background: var(--accent); color: var(--accent-ink); font-weight: 700; text-decoration: none; padding: 12px 20px; border-radius: 8px; margin: 8px 0; }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(210px, 1fr)); gap: 12px; }
.grid a.card { display: block; margin: 0; text-decoration: none; color: var(--text); }
.grid a.card strong { display: block; color: var(--accent); margin-bottom: 4px; }
table { width: 100%; border-collapse: collapse; font-size: 16px; }
th, td { text-align: left; padding: 8px 6px; border-bottom: 1px solid var(--line); vertical-align: top; }
.calc label { display: block; font-size: 15px; color: var(--muted); margin-top: 10px; }
.calc input, .calc select { width: 100%; font: inherit; padding: 8px 10px; border: 1px solid var(--line); border-radius: 6px; background: var(--bg); color: var(--text); }
.calc .row { display: grid; grid-template-columns: 1fr 1fr; gap: 0 12px; }
.calc output { display: block; margin-top: 16px; }
.calc .big { font-size: 22px; font-weight: 700; }
details { border-bottom: 1px solid var(--line); padding: 10px 0; }
summary { cursor: pointer; font-weight: 600; }
footer.site { border-top: 1px solid var(--line); background: var(--surface); font-size: 14px; color: var(--muted); }
footer.site .wrap { padding-top: 20px; padding-bottom: 28px; }
footer.site a { color: var(--muted); }
footer.site nav { display: flex; flex-wrap: wrap; gap: 4px 16px; margin-bottom: 10px; }
@media (max-width: 520px) {
  h1 { font-size: 27px; }
  .calc .row { grid-template-columns: 1fr; }
}