:root {
  --ink: #1d1d1f; --soft: #6e6e73; --faint: #a1a1a6; --line: #d2d2d7;
  --panel: #f5f5f7; --bg: #fbfbfd; --surface: #ffffff;
  --accent: #0071e3; --tint: #e8f2fd; --danger: #d70015; --ok: #1a7f37;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0; background: var(--bg); color: var(--ink);
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Arial, sans-serif;
  font-size: 17px; line-height: 1.65; -webkit-font-smoothing: antialiased;
}
a { color: var(--accent); }
img, svg { max-width: 100%; }
::selection { background: #cfe6fd; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* Header */
.site-header {
  position: sticky; top: 0; z-index: 40;
  background: rgba(251,251,253,0.85); backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--line);
}
.site-header .bar {
  max-width: 1180px; margin: 0 auto; padding: 0 24px; height: 56px;
  display: flex; align-items: center; gap: 28px;
}
.brand {
  display: flex; align-items: center; gap: 8px; font-size: 18px; font-weight: 700;
  letter-spacing: -0.02em; color: var(--ink); text-decoration: none;
}
.site-nav { display: flex; gap: 22px; flex: 1; }
.site-nav a { font-size: 13.5px; color: var(--soft); text-decoration: none; }
.site-nav a:hover { color: var(--ink); }
.btn {
  display: inline-block; background: var(--accent); color: #fff !important; text-decoration: none;
  border: 0; border-radius: 999px; padding: 11px 22px; font: inherit; font-size: 15px; font-weight: 600; cursor: pointer;
}
.btn:hover { background: #0062c8; }
.btn.small { padding: 9px 18px; font-size: 13.5px; white-space: nowrap; }
.btn.ghost { background: transparent; color: var(--accent) !important; border: 1px solid var(--accent); }
@media (max-width: 780px) {
  .site-header .bar { gap: 14px; padding: 0 16px; }
  .site-nav { gap: 16px; }
  .site-nav .hide-sm { display: none; }
  .site-header .btn.small { padding: 8px 12px; font-size: 12.5px; }
}

/* Layout */
.wrap { max-width: 1180px; margin: 0 auto; padding: 0 24px; }
.article { max-width: 760px; margin: 0 auto; padding: 36px 24px 72px; }
@media (max-width: 480px) { .hide-xs { display: none; } .article { padding: 28px 16px 56px; } .wrap { padding: 0 16px; } }
.crumbs { font-size: 13px; color: var(--soft); margin: 0 0 14px; }
.crumbs a { color: var(--soft); text-decoration: none; }
.crumbs a:hover { text-decoration: underline; }
h1 { font-size: clamp(30px, 5vw, 44px); line-height: 1.12; letter-spacing: -0.03em; margin: 0 0 14px; }
h2 { font-size: clamp(22px, 3vw, 28px); line-height: 1.2; letter-spacing: -0.02em; margin: 44px 0 12px; }
h3 { font-size: 18px; margin: 26px 0 8px; letter-spacing: -0.01em; }
p { margin: 0 0 16px; }
.lead { font-size: 19px; color: #3a3a3d; }
.meta { font-size: 13px; color: var(--soft); margin: 0 0 26px; }
ul, ol { padding-left: 22px; margin: 0 0 18px; }
li { margin-bottom: 8px; }
code, pre { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 0.92em; }
.prompt {
  background: var(--panel); border: 1px solid var(--line); border-left: 3px solid var(--accent);
  border-radius: 10px; padding: 14px 16px; margin: 0 0 16px; white-space: pre-wrap; font-size: 15px; line-height: 1.55;
}

/* Tables */
.tbl { width: 100%; border-collapse: collapse; margin: 0 0 22px; font-size: 15px; }
.tbl th, .tbl td { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--line); vertical-align: top; }
.tbl thead th { background: var(--panel); font-size: 13px; color: var(--soft); text-transform: uppercase; letter-spacing: 0.04em; }
.tbl-wrap { overflow-x: auto; -webkit-overflow-scrolling: touch; }

/* Callouts */
.callout {
  background: var(--tint); border-radius: 14px; padding: 16px 18px; margin: 0 0 22px; font-size: 15.5px;
}
.callout.warn { background: #fff4e5; }
.callout p:last-child { margin-bottom: 0; }
.cta {
  background: var(--ink); color: #fff; border-radius: 20px; padding: 30px 28px; margin: 44px 0 0;
}
.cta h2 { color: #fff; margin: 0 0 8px; font-size: 24px; }
.cta p { color: #d2d2d7; margin: 0 0 18px; }
.sources { font-size: 14px; color: var(--soft); border-top: 1px solid var(--line); margin-top: 40px; padding-top: 18px; }
.sources h2 { font-size: 16px; margin: 0 0 8px; letter-spacing: 0; }
.sources li { margin-bottom: 4px; }

/* Cards */
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 16px; margin: 24px 0 0; }
.card {
  display: block; background: var(--surface); border: 1px solid var(--line); border-radius: 18px;
  padding: 22px; text-decoration: none; color: var(--ink);
}
.card:hover { border-color: var(--accent); box-shadow: 0 6px 24px rgba(0,0,0,0.06); }
.card h3 { margin: 0 0 8px; font-size: 18px; }
.card p { margin: 0; font-size: 14.5px; color: var(--soft); }
.card .tag { font-size: 12px; font-weight: 600; color: var(--accent); margin-bottom: 8px; display: block; }

/* Calculator */
.calc {
  background: var(--surface); border: 1px solid var(--line); border-radius: 20px; padding: 24px; margin: 0 0 26px;
}
.calc label { display: block; font-size: 14px; font-weight: 600; margin: 0 0 6px; }
.calc .hint { display: block; font-size: 12.5px; font-weight: 400; color: var(--soft); margin-top: 2px; }
.calc .field { margin-bottom: 16px; }
.calc input, .calc select {
  width: 100%; font: inherit; font-size: 17px; padding: 12px 14px; border: 1px solid var(--line);
  border-radius: 12px; background: #fff; color: var(--ink);
}
.calc .grid2 { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
@media (max-width: 560px) { .calc .grid2 { grid-template-columns: 1fr; } }
.calc-headline {
  background: var(--tint); border-radius: 14px; padding: 16px 18px; margin: 4px 0 16px;
  display: flex; flex-direction: column; gap: 2px;
}
.calc-headline span { font-size: 13.5px; color: var(--soft); }
.calc-headline strong { font-size: clamp(26px, 6vw, 34px); letter-spacing: -0.02em; color: var(--accent); }
.calc-table { width: 100%; border-collapse: collapse; font-size: 15px; }
.calc-table th { text-align: left; font-weight: 500; padding: 9px 0; border-bottom: 1px solid var(--line); }
.calc-table td { text-align: right; padding: 9px 0; border-bottom: 1px solid var(--line); white-space: nowrap; padding-left: 12px; }
.calc-table tr.sub th, .calc-table tr.sub td { color: var(--soft); font-size: 14px; }
.calc-table tr.total th, .calc-table tr.total td { font-weight: 700; }
.calc-table tr.net td { color: var(--accent); }
.calc-note { font-size: 13.5px; color: var(--soft); margin: 14px 0 0; }

/* Footer */
.site-footer { border-top: 1px solid var(--line); background: var(--panel); padding: 40px 24px; text-align: center; margin-top: 40px; }
.site-footer .links { display: flex; gap: 20px; justify-content: center; flex-wrap: wrap; margin: 0 0 14px; font-size: 14px; }
.site-footer .links a { color: var(--ink); text-decoration: none; }
.site-footer .links a:hover { text-decoration: underline; }
.site-footer p { font-size: 12.5px; color: var(--faint); margin: 0; }
.hub-head { padding: 44px 0 8px; }