@font-face {
  font-family: "Manrope";
  src: url(fonts/manrope-400.woff2) format("woff2");
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: "Manrope";
  src: url(fonts/manrope-700.woff2) format("woff2");
  font-weight: 700;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: "Manrope";
  src: url(fonts/manrope-800.woff2) format("woff2");
  font-weight: 800;
  font-style: normal;
  font-display: swap;
}

:root {
  --ink: #1f2933;
  --muted: #5f6b76;
  --paper: #faf7f2;
  --card: #ffffff;
  --line: #e4ddd2;
  --accent: #b4552d;
  --accent-dark: #8f3f1f;
  --green: #2f5d4a;
  --green-soft: #e7efe9;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(31, 41, 51, 0.08);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "Manrope", system-ui, -apple-system, "Segoe UI", sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.6;
  font-size: 17px;
}

a { color: var(--accent-dark); }
a:hover { color: var(--accent); }

.wrap {
  width: min(1080px, calc(100% - 40px));
  margin: 0 auto;
}

header.site {
  background: var(--paper);
  border-bottom: 1px solid var(--line);
}
header.site .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 64px;
}
.brand {
  font-weight: 800;
  font-size: 21px;
  letter-spacing: -0.02em;
  color: var(--ink);
  text-decoration: none;
}
.brand span { color: var(--accent); }
nav.main {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 18px;
  font-size: 15px;
  font-weight: 700;
}
nav.main a {
  color: var(--muted);
  text-decoration: none;
  padding: 6px 0;
}
nav.main a:hover, nav.main a[aria-current="page"] { color: var(--ink); }

.hero {
  padding: 46px 0 10px;
}
.hero .kicker {
  display: inline-block;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 10px;
}
.hero h1 {
  font-size: clamp(32px, 5vw, 52px);
  line-height: 1.08;
  letter-spacing: -0.03em;
  margin: 0 0 14px;
  max-width: 780px;
}
.hero p.lead {
  font-size: 19px;
  color: var(--muted);
  max-width: 680px;
  margin: 0 0 8px;
}

.calc {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 22px;
  align-items: start;
  margin: 26px 0 10px;
}
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
}
.card h2 {
  font-size: 18px;
  margin: 0 0 16px;
  letter-spacing: -0.01em;
}
.field {
  display: grid;
  grid-template-columns: 1fr 150px;
  gap: 12px;
  align-items: center;
  padding: 9px 0;
  border-bottom: 1px solid #f1ece4;
}
.field:last-of-type { border-bottom: 0; }
.field label { font-weight: 700; font-size: 15px; }
.field .hint {
  display: block;
  font-weight: 400;
  font-size: 13px;
  color: var(--muted);
}
.field input, .field select {
  width: 100%;
  font: inherit;
  font-variant-numeric: tabular-nums;
  text-align: right;
  padding: 9px 11px;
  border: 1px solid #d8d0c3;
  border-radius: 9px;
  background: #fffdf9;
  color: var(--ink);
}
.field select { text-align: left; }
.field input:focus, .field select:focus {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
}
.field .unit {
  font-size: 13px;
  color: var(--muted);
  text-align: right;
  margin-top: -6px;
}
.row-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}
.row-2 .field { grid-template-columns: 1fr; gap: 4px; }

.result {
  background: var(--green);
  color: #fff;
  border-radius: var(--radius);
  padding: 24px;
  position: sticky;
  top: 84px;
}
.result h2 { color: #fff; margin: 0 0 14px; font-size: 18px; }
.result .big {
  font-size: 46px;
  font-weight: 800;
  line-height: 1;
  letter-spacing: -0.03em;
}
.result .big small { font-size: 18px; font-weight: 700; letter-spacing: 0; }
.result .sub { color: #d8e6dd; font-size: 14px; margin-top: 4px; }
.result dl {
  margin: 18px 0 0;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 8px 14px;
  font-size: 15px;
}
.result dt { color: #d8e6dd; }
.result dd { margin: 0; font-weight: 800; text-align: right; font-variant-numeric: tabular-nums; }
.result .note {
  margin-top: 18px;
  padding-top: 14px;
  border-top: 1px solid rgba(255,255,255,0.22);
  font-size: 13px;
  color: #d8e6dd;
}
.result button {
  margin-top: 16px;
  width: 100%;
  font: inherit;
  font-weight: 800;
  padding: 11px 14px;
  border: 0;
  border-radius: 9px;
  background: #fff;
  color: var(--green);
  cursor: pointer;
}
.result button:hover { background: #f2f7f3; }

article.body {
  max-width: 760px;
  margin: 34px 0 60px;
}
article.body h2 {
  font-size: 26px;
  letter-spacing: -0.02em;
  margin: 38px 0 10px;
}
article.body h3 {
  font-size: 19px;
  margin: 24px 0 6px;
}
article.body p, article.body li { color: #33404b; }
article.body ul { padding-left: 22px; }
article.body .example {
  background: var(--green-soft);
  border-left: 4px solid var(--green);
  border-radius: 0 10px 10px 0;
  padding: 16px 18px;
  margin: 18px 0;
}
article.body .example p { margin: 0; }
.formula {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  background: #f3eee6;
  border: 1px solid var(--line);
  border-radius: 9px;
  padding: 12px 14px;
  font-size: 14px;
  overflow-x: auto;
}
details.faq {
  border-bottom: 1px solid var(--line);
  padding: 14px 0;
}
details.faq summary {
  cursor: pointer;
  font-weight: 800;
  font-size: 17px;
}
details.faq p { margin: 10px 0 0; }

footer.site {
  background: var(--ink);
  color: #c9d2d9;
  padding: 30px 0;
  font-size: 14px;
}
footer.site .wrap {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 14px;
}
footer.site a { color: #e7efe9; text-decoration: none; }
footer.site a:hover { text-decoration: underline; }

@media (max-width: 880px) {
  .calc { grid-template-columns: 1fr; }
  .result { position: static; }
  .field { grid-template-columns: 1fr 130px; }
}
@media (max-width: 560px) {
  body { font-size: 16px; }
  .wrap { width: calc(100% - 28px); }
  header.site .wrap { min-height: 58px; flex-wrap: wrap; gap: 4px 14px; padding: 8px 0; }
  .brand { font-size: 18px; }
  nav.main { font-size: 14px; gap: 4px 12px; }
  .hero { padding-top: 30px; }
  .card { padding: 18px; }
  .field { grid-template-columns: 1fr; gap: 4px; }
  .field input, .field select { text-align: left; }
  .field .unit { text-align: left; margin-top: 0; }
  .row-2 { grid-template-columns: 1fr; }
  .result .big { font-size: 40px; }
}
@media print {
  header.site, footer.site, .hero .kicker, .result button, nav.main { display: none; }
  body { background: #fff; }
  .calc { grid-template-columns: 1fr; }
  .result { background: #fff; color: #000; border: 1px solid #000; position: static; }
  .result h2, .result .sub, .result dt, .result .note { color: #000; }
  .result dd { color: #000; }
  .card { box-shadow: none; }
}