:root {
  --bg: #f7f7f4;
  --card: #ffffff;
  --text: #1c1f23;
  --muted: #5b636d;
  --line: #dfe2e6;
  --accent: #1d4ed8;
  --accent-ink: #ffffff;
  --good: #047857;
  --bad: #b91c1c;
  --soft: #eef2ff;
  --radius: 10px;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111418;
    --card: #1a1e24;
    --text: #e8eaed;
    --muted: #a3abb5;
    --line: #2e343c;
    --accent: #7aa2ff;
    --accent-ink: #0b1020;
    --good: #34d399;
    --bad: #f87171;
    --soft: #1e2638;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}
a { color: var(--accent); }
.wrap { max-width: 980px; margin: 0 auto; padding: 0 16px; }
.top { border-bottom: 1px solid var(--line); background: var(--card); }
.top .wrap { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 20px; padding-top: 10px; padding-bottom: 10px; }
.brand { font-weight: 700; color: var(--text); text-decoration: none; display: inline-flex; align-items: center; gap: 8px; }
.brand svg { width: 24px; height: 24px; }
.top nav { display: flex; flex-wrap: wrap; gap: 4px 14px; font-size: 14px; }
.top nav a { text-decoration: none; color: var(--muted); }
.top nav a[aria-current="page"] { color: var(--text); font-weight: 600; }
main { padding: 24px 0 48px; }
h1 { font-size: clamp(1.6rem, 4.5vw, 2.2rem); line-height: 1.2; margin: 0 0 8px; }
h2 { font-size: 1.3rem; margin: 32px 0 8px; }
h3 { font-size: 1.05rem; margin: 20px 0 6px; }
.lead { color: var(--muted); font-size: 1.05rem; margin-top: 0; }
.calc { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 20px; margin: 20px 0; }
@media (max-width: 760px) { .calc { grid-template-columns: minmax(0, 1fr); } }
.panel { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px; min-width: 0; }
.panel h2 { margin-top: 0; font-size: 1.1rem; }
.field { display: block; margin-bottom: 12px; }
.field > span { display: block; font-size: 14px; font-weight: 600; margin-bottom: 4px; }
.field small { display: block; color: var(--muted); font-size: 13px; font-weight: 400; }
input[type="number"], select {
  width: 100%;
  font: inherit;
  padding: 8px 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--bg);
  color: var(--text);
}
input:focus-visible, select:focus-visible, a:focus-visible, summary:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.check { display: flex; gap: 8px; align-items: flex-start; font-size: 14px; margin-bottom: 12px; }
.check input { margin-top: 4px; }
.row2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(120px, 1fr)); gap: 0 12px; }
.results dl { margin: 0; }
.results .kpi { display: flex; justify-content: space-between; gap: 12px; padding: 8px 0; border-bottom: 1px solid var(--line); }
.results .kpi:last-child { border-bottom: 0; }
.results dt { color: var(--muted); font-size: 14px; }
.results dd { margin: 0; font-weight: 700; text-align: right; font-variant-numeric: tabular-nums; }
.results .big dd { font-size: 1.4rem; color: var(--accent); }
.verdict { margin: 12px 0 0; padding: 10px 12px; border-radius: 8px; background: var(--soft); font-size: 14px; }
.error { color: var(--bad); font-weight: 600; font-size: 14px; min-height: 1em; margin: 8px 0 0; }
.formula { background: var(--card); border: 1px solid var(--line); border-left: 4px solid var(--accent); border-radius: 8px; padding: 10px 14px; overflow-x: auto; font-family: ui-monospace, SFMono-Regular, Consolas, monospace; font-size: 14px; white-space: pre-wrap; }
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); background: var(--card); }
table { border-collapse: collapse; width: 100%; font-size: 14px; }
th, td { padding: 8px 10px; border-bottom: 1px solid var(--line); text-align: right; white-space: nowrap; font-variant-numeric: tabular-nums; }
th:first-child, td:first-child { text-align: left; }
thead th { background: var(--soft); }
tbody tr:last-child td { border-bottom: 0; }
tr.sel td { font-weight: 700; }
.small { font-size: 13px; color: var(--muted); }
details { background: var(--card); border: 1px solid var(--line); border-radius: 8px; padding: 10px 14px; margin: 8px 0; }
summary { cursor: pointer; font-weight: 600; }
details p { margin: 8px 0 0; }
.cta { margin: 32px 0; padding: 20px; border-radius: var(--radius); border: 2px solid var(--accent); background: var(--soft); }
.cta h2 { margin-top: 0; }
.cta ul { padding-left: 20px; }
.btn { display: inline-block; background: var(--accent); color: var(--accent-ink); font-weight: 700; padding: 10px 18px; border-radius: 8px; text-decoration: none; }
.btn:hover { filter: brightness(1.08); }
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px; margin: 20px 0; }
.card { display: block; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px; text-decoration: none; color: var(--text); }
.card:hover { border-color: var(--accent); }
.card strong { display: block; color: var(--accent); margin-bottom: 4px; }
.card span { color: var(--muted); font-size: 14px; }
.related { padding-left: 20px; }
footer { border-top: 1px solid var(--line); padding: 20px 0 32px; font-size: 13px; color: var(--muted); }
footer a { color: var(--muted); }