:root {
  --ink: #17332d;
  --muted: #61736d;
  --paper: #f6f4eb;
  --card: #fffefa;
  --green: #176b55;
  --green-dark: #0d493a;
  --lime: #d9f05b;
  --line: #d8ded8;
  --shadow: 0 18px 50px rgba(23, 51, 45, 0.09);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.65;
}
a { color: var(--green); }
a:hover { color: var(--green-dark); }
.wrap { width: min(1120px, calc(100% - 36px)); margin-inline: auto; }
.site-header { background: rgba(246, 244, 235, .94); border-bottom: 1px solid var(--line); position: sticky; top: 0; z-index: 10; backdrop-filter: blur(12px); }
.nav { min-height: 72px; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.brand { color: var(--ink); text-decoration: none; font-weight: 850; letter-spacing: -.04em; font-size: 1.25rem; }
.brand span { color: var(--green); }
.nav-links { display: flex; gap: 22px; align-items: center; }
.nav-links a { color: var(--ink); text-decoration: none; font-size: .94rem; font-weight: 650; }
.hero { padding: 74px 0 52px; }
.eyebrow { text-transform: uppercase; letter-spacing: .13em; font-size: .76rem; font-weight: 800; color: var(--green); }
h1, h2, h3 { line-height: 1.12; letter-spacing: -.035em; }
h1 { font-size: clamp(2.55rem, 6vw, 5.2rem); max-width: 900px; margin: 15px 0 24px; }
h2 { font-size: clamp(1.75rem, 3vw, 2.65rem); margin: 0 0 16px; }
h3 { font-size: 1.25rem; }
.lede { font-size: 1.18rem; color: var(--muted); max-width: 720px; }
.actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 28px; }
.button { display: inline-flex; justify-content: center; align-items: center; min-height: 48px; padding: 0 20px; border-radius: 10px; background: var(--green); color: white; text-decoration: none; font-weight: 750; border: 0; cursor: pointer; }
.button:hover { background: var(--green-dark); color: white; }
.button.secondary { background: transparent; color: var(--ink); border: 1px solid var(--line); }
.stat-strip { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: 16px; overflow: hidden; margin: 28px auto 72px; }
.stat { padding: 24px; background: var(--card); }
.stat strong { display: block; font-size: 1.25rem; }
.stat span { color: var(--muted); font-size: .9rem; }
.section { padding: 64px 0; }
.section.white { background: var(--card); border-block: 1px solid var(--line); }
.grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 16px; padding: 26px; box-shadow: var(--shadow); }
.card p { color: var(--muted); }
.card .status { display: inline-block; padding: 4px 9px; border-radius: 999px; background: #edf2ed; color: var(--muted); font-size: .76rem; font-weight: 750; }
.card.featured { border-top: 5px solid var(--lime); }
.article { max-width: 760px; padding: 60px 0 80px; }
.article h1 { font-size: clamp(2.3rem, 5vw, 4.2rem); }
.article h2 { margin-top: 48px; }
.article li + li { margin-top: 8px; }
.calculator-layout { display: grid; grid-template-columns: minmax(0, 1.12fr) minmax(300px, .88fr); gap: 24px; align-items: start; margin-top: 30px; }
.calculator { background: var(--card); padding: 28px; border: 1px solid var(--line); border-radius: 18px; box-shadow: var(--shadow); }
.field-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
label { font-weight: 750; font-size: .92rem; display: block; }
label small { display: block; color: var(--muted); font-weight: 450; margin-top: 3px; }
input, select { width: 100%; min-height: 48px; margin-top: 7px; padding: 10px 12px; border: 1px solid #bac7c1; border-radius: 9px; background: white; color: var(--ink); font: inherit; }
input:focus, select:focus { outline: 3px solid rgba(217, 240, 91, .7); border-color: var(--green); }
.result { background: var(--green-dark); color: white; padding: 28px; border-radius: 18px; position: sticky; top: 96px; }
.result .big { font-size: clamp(2.4rem, 5vw, 4rem); font-weight: 850; line-height: 1; margin: 12px 0 8px; letter-spacing: -.05em; }
.result .sub { color: #c9ddd6; }
.result-list { list-style: none; padding: 0; margin: 24px 0 0; border-top: 1px solid rgba(255,255,255,.2); }
.result-list li { display: flex; justify-content: space-between; gap: 20px; padding: 13px 0; border-bottom: 1px solid rgba(255,255,255,.14); }
.formula { background: #edf2ed; padding: 18px; border-radius: 12px; overflow-x: auto; }
.notice { border-left: 4px solid var(--lime); background: #f1f6d6; padding: 16px 18px; margin: 28px 0; }
.breadcrumbs { color: var(--muted); font-size: .86rem; margin-bottom: 24px; }
.breadcrumbs a { color: var(--muted); }
.breadcrumbs span { margin-inline: 7px; }
.meta-line { display: flex; flex-wrap: wrap; gap: 8px 18px; color: var(--muted); font-size: .88rem; margin: -8px 0 28px; }
.source-list { padding-left: 20px; }
.source-list li + li { margin-top: 10px; }
.cluster-links { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; margin: 26px 0; }
.cluster-links a { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 14px 16px; text-decoration: none; font-weight: 700; }
.table-wrap { overflow-x: auto; margin: 24px 0; }
table { width: 100%; border-collapse: collapse; background: var(--card); }
th, td { text-align: left; border: 1px solid var(--line); padding: 12px 14px; vertical-align: top; }
th { background: #edf2ed; }
.result-note { color: #c9ddd6; font-size: .84rem; margin-top: 14px; }
.update-log { border-top: 1px solid var(--line); margin-top: 46px; padding-top: 22px; color: var(--muted); }
.faq details { border-top: 1px solid var(--line); padding: 16px 0; }
.faq details:last-child { border-bottom: 1px solid var(--line); }
.faq summary { cursor: pointer; font-weight: 750; }
.faq details p { margin-bottom: 0; }
.footer { border-top: 1px solid var(--line); padding: 36px 0; color: var(--muted); }
.footer-inner { display: flex; justify-content: space-between; gap: 28px; flex-wrap: wrap; }
.footer-links { display: flex; gap: 18px; flex-wrap: wrap; }
.footer a { color: var(--muted); }

@media (max-width: 780px) {
  .nav-links a:not(:last-child) { display: none; }
  .hero { padding-top: 48px; }
  .grid, .stat-strip, .calculator-layout { grid-template-columns: 1fr; }
  .cluster-links { grid-template-columns: 1fr; }
  .field-grid { grid-template-columns: 1fr; }
  .result { position: static; }
}