:root {
  --ink: #082d3a; --ink-soft: #425c64; --paper: #f7fbfa; --white: #fff;
  --line: #cbdad8; --teal: #087f75; --teal-dark: #05685f; --mint: #d8f3ec;
  --mint-bright: #68d5bd; --sky: #8ccde0; --amber: #efb357; --coral: #db746b;
  --shadow: 0 24px 70px rgba(8,45,58,.13); --radius-lg: 1.5rem; --radius-md: .875rem;
}
* { box-sizing: border-box; }
[hidden] { display: none !important; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--paper); color: var(--ink); font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; font-size: 1rem; line-height: 1.6; -webkit-font-smoothing: antialiased; }
button, input { font: inherit; }
a { color: var(--teal-dark); text-underline-offset: .2em; }
a:hover { color: var(--ink); }
.shell { width: min(1180px, calc(100% - 2rem)); margin-inline: auto; }
.narrow-shell { width: min(1040px, calc(100% - 2rem)); }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }
.skip-link { position: fixed; left: 1rem; top: 1rem; z-index: 100; padding: .75rem 1rem; background: var(--white); color: var(--ink); border-radius: .5rem; transform: translateY(-200%); }
.skip-link:focus { transform: translateY(0); }

.site-header { position: relative; z-index: 10; background: #06313e; color: var(--white); border-bottom: 1px solid rgba(255,255,255,.12); }
.header-inner { min-height: 74px; display: flex; align-items: center; justify-content: space-between; gap: 2rem; }
.brand { display: inline-flex; align-items: center; gap: .75rem; color: inherit; text-decoration: none; font-weight: 760; letter-spacing: -.02em; }
.brand-mark { display: grid; place-items: center; width: 2rem; height: 2rem; border: 2px solid var(--mint-bright); border-radius: 50% 50% 50% 0; color: var(--mint-bright); font-size: .9rem; transform: rotate(-8deg); }
.brand-mark::first-letter { transform: rotate(8deg); }
.site-header nav { display: flex; align-items: center; gap: 1.75rem; }
.site-header nav a { color: rgba(255,255,255,.78); text-decoration: none; font-size: .92rem; }
.site-header nav a:hover, .site-header nav a:focus-visible { color: var(--white); }

.calculator-section { position: relative; overflow: hidden; padding: 4.5rem 0 2rem; background: radial-gradient(circle at 86% 4%, rgba(104,213,189,.2), transparent 28rem), linear-gradient(180deg, #06313e 0, #06313e 55%, var(--paper) 55%); }
.calculator-section::before { content: ""; position: absolute; width: 360px; height: 360px; left: -190px; top: 80px; border: 1px solid rgba(140,205,224,.17); border-radius: 50%; box-shadow: 0 0 0 70px rgba(140,205,224,.04); }
.intro { position: relative; max-width: 700px; color: var(--white); margin-bottom: 2rem; }
.eyebrow { margin: 0 0 .65rem; color: var(--teal); font-size: .78rem; font-weight: 800; letter-spacing: .14em; text-transform: uppercase; }
.intro .eyebrow { color: var(--mint-bright); }
h1, h2, h3 { margin-top: 0; line-height: 1.12; letter-spacing: -.035em; }
h1 { margin-bottom: .75rem; font-size: clamp(2.6rem, 7vw, 4.9rem); font-weight: 760; }
h2 { margin-bottom: 1rem; font-size: clamp(2rem, 4vw, 3.25rem); }
h3 { margin-bottom: .65rem; font-size: 1.18rem; }
.intro-copy { max-width: 620px; margin: 0; color: rgba(255,255,255,.75); font-size: clamp(1rem,2vw,1.15rem); }

.calculator-grid { position: relative; display: grid; grid-template-columns: minmax(0,.9fr) minmax(0,1.1fr); border-radius: var(--radius-lg); box-shadow: var(--shadow); overflow: hidden; }
.calculator-card { padding: clamp(1.4rem,4vw,2.5rem); background: var(--white); }
.result-card { padding: clamp(1.5rem,4vw,2.75rem); background: #e9f7f3; border-left: 1px solid #cde4de; }
.unit-switcher { margin: 0 0 2rem; padding: 0; border: 0; }
.unit-switcher legend { margin-bottom: .65rem; font-size: .88rem; font-weight: 700; }
.segmented-control { display: grid; grid-template-columns: 1fr 1fr; padding: .25rem; border-radius: .8rem; background: #eaf0ef; }
.segmented-control label { cursor: pointer; }
.segmented-control input { position: absolute; opacity: 0; }
.segmented-control span { display: block; padding: .65rem .75rem; border-radius: .6rem; text-align: center; color: var(--ink-soft); font-weight: 700; font-size: .92rem; }
.segmented-control input:checked + span { background: var(--white); color: var(--ink); box-shadow: 0 2px 8px rgba(8,45,58,.12); }
.segmented-control input:focus-visible + span { outline: 3px solid rgba(8,127,117,.28); outline-offset: 2px; }
.field-set { display: grid; grid-template-columns: 1fr 1fr; gap: 1.2rem; }
.stacked-groups { grid-template-columns: 1fr; }
.measurement-group + .measurement-group { margin-top: .25rem; }
.group-label, .field > label { display: block; margin-bottom: .45rem; color: var(--ink); font-size: .88rem; font-weight: 740; }
.paired-fields { display: grid; grid-template-columns: 1fr 1fr; gap: .8rem; }
.input-with-unit { display: flex; align-items: center; min-height: 56px; border: 1px solid var(--line); border-radius: .75rem; background: #fbfdfd; transition: border-color 160ms, box-shadow 160ms; }
.input-with-unit:focus-within { border-color: var(--teal); box-shadow: 0 0 0 4px rgba(8,127,117,.12); }
.input-with-unit input { min-width: 0; width: 100%; padding: .8rem .25rem .8rem .9rem; border: 0; outline: 0; color: var(--ink); background: transparent; font-size: 1.05rem; font-weight: 700; }
.input-with-unit span { padding-right: .9rem; color: var(--ink-soft); font-size: .85rem; font-weight: 700; }
.field small { display: block; margin-top: .4rem; color: #6a7c81; font-size: .75rem; }
.form-error { margin: 1rem 0 0; padding: .7rem .9rem; border-radius: .6rem; background: #fff0ee; color: #8b2f29; font-size: .88rem; }
.primary-button { width: 100%; min-height: 54px; margin-top: 1.75rem; border: 0; border-radius: .75rem; background: var(--teal); color: var(--white); font-weight: 800; cursor: pointer; box-shadow: 0 10px 24px rgba(8,127,117,.2); transition: background 160ms, transform 160ms, box-shadow 160ms; }
.primary-button:hover { background: var(--teal-dark); box-shadow: 0 13px 26px rgba(8,127,117,.25); transform: translateY(-1px); }
.primary-button:focus-visible { outline: 3px solid rgba(8,127,117,.28); outline-offset: 3px; }
.privacy-note { display: flex; align-items: center; justify-content: center; gap: .45rem; margin: .9rem 0 0; color: #64777c; font-size: .78rem; }
.privacy-note svg, .result-note svg { fill: currentColor; flex: 0 0 auto; }

.result-label { margin: 0 0 .25rem; color: var(--ink-soft); font-size: .82rem; font-weight: 800; letter-spacing: .1em; text-transform: uppercase; }
.result-heading-row { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 1rem; }
.result-heading-row h2 { margin: 0; font-size: clamp(2.5rem,6vw,4.4rem); }
.category-badge { display: inline-flex; align-items: center; min-height: 34px; padding: .35rem .75rem; border: 1px solid #65ab9b; border-radius: 999px; background: #d9f4eb; color: #075f56; font-size: .83rem; font-weight: 800; }
.category-badge[data-category="underweight"] { border-color: #68a9bd; background: #dff3f8; color: #235b6b; }
.category-badge[data-category="overweight"] { border-color: #c98b30; background: #fff1d6; color: #774d0f; }
.category-badge[data-category="obesity"] { border-color: #bd5e55; background: #fde5e2; color: #7b302a; }
.scale-wrap { position: relative; margin: 2.3rem 0 1.7rem; padding-top: .9rem; }
.bmi-scale { display: grid; grid-template-columns: 22% 32% 22% 24%; height: 10px; overflow: hidden; border-radius: 99px; }
.bmi-scale span { display: block; }
.under { background: var(--sky); } .healthy { background: var(--mint-bright); } .over { background: var(--amber); } .obese { background: var(--coral); }
.scale-marker { position: absolute; z-index: 2; top: .42rem; left: var(--marker-position); width: 18px; height: 18px; border: 3px solid var(--white); border-radius: 50%; background: var(--ink); box-shadow: 0 2px 7px rgba(8,45,58,.35); transform: translateX(-50%); transition: left 350ms ease; }
.scale-labels { display: grid; grid-template-columns: 22% 32% 22% 24%; margin-top: .4rem; color: #5f7479; font-size: .68rem; }
.scale-labels span:nth-child(n+2) { text-align: center; }
.scale-labels span:last-child { text-align: right; }
.result-summary { display: grid; grid-template-columns: 1fr 1fr; gap: 1.5rem; padding: 1.5rem 0; border-top: 1px solid #c8dfda; border-bottom: 1px solid #c8dfda; }
.summary-label { display: block; margin-bottom: .3rem; color: var(--ink-soft); font-size: .78rem; font-weight: 700; }
.result-summary strong { font-size: 1.1rem; }
.result-summary p { margin: 0; color: var(--ink-soft); font-size: .9rem; }
.result-note { display: flex; gap: .7rem; margin-top: 1.5rem; color: var(--ink-soft); }
.result-note svg { margin-top: .15rem; color: var(--teal); }
.result-note p { margin: 0; font-size: .82rem; }
.adult-notice { max-width: 920px; margin: 1.15rem auto 0; color: #61757a; text-align: center; font-size: .8rem; }

.content-section { padding: clamp(4.5rem,9vw,7rem) 0; background: var(--white); }
.section-lead { max-width: 700px; margin: 0 0 2.5rem; color: var(--ink-soft); font-size: 1.08rem; }
.formula-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1.25rem; }
.formula-card { position: relative; padding: 2rem; overflow: hidden; border: 1px solid var(--line); border-radius: var(--radius-md); background: var(--paper); }
.formula-number { position: absolute; right: 1.3rem; top: .65rem; color: rgba(8,45,58,.08); font-size: 4.2rem; font-weight: 900; line-height: 1; }
.formula-card p { margin-bottom: 0; color: var(--ink-soft); }
.formula-card .formula { margin: 1.5rem 0 .25rem; color: var(--teal-dark); font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: clamp(1.25rem,3vw,1.7rem); font-weight: 800; }
.muted-section { background: #edf5f3; }
.section-heading-row { display: grid; grid-template-columns: 1fr .8fr; align-items: end; gap: 4rem; margin-bottom: 2.5rem; }
.section-heading-row h2 { margin-bottom: 0; }
.section-heading-row > p { margin: 0; color: var(--ink-soft); }
.category-table { border: 1px solid #bfd3cf; border-radius: var(--radius-md); overflow: hidden; background: var(--white); }
.table-row { display: grid; grid-template-columns: 1fr 1fr; padding: 1rem 1.3rem; border-top: 1px solid #d9e5e3; }
.table-row:first-child { border-top: 0; }
.table-head { background: #0a3a46; color: var(--white); font-size: .78rem; font-weight: 800; letter-spacing: .08em; text-transform: uppercase; }
.table-row strong { text-align: right; }
.dot { display: inline-block; width: .65rem; height: .65rem; margin-right: .7rem; border-radius: 50%; }
.dot-under { background: var(--sky); } .dot-healthy { background: var(--mint-bright); } .dot-over { background: var(--amber); } .dot-obese { background: var(--coral); }
.limitations-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 1rem; margin-top: 2rem; }
.limitations-grid article { padding: 1.4rem; border-left: 3px solid var(--teal); background: rgba(255,255,255,.54); }
.limitations-grid p { margin: 0; color: var(--ink-soft); font-size: .9rem; }
.faq-layout { display: grid; grid-template-columns: .65fr 1.35fr; gap: 5rem; align-items: start; }
.faq-intro { position: sticky; top: 2rem; }
.faq-intro p:last-child { color: var(--ink-soft); }
.faq-list details { border-top: 1px solid var(--line); }
.faq-list details:last-child { border-bottom: 1px solid var(--line); }
.faq-list summary { position: relative; padding: 1.3rem 2.5rem 1.3rem 0; cursor: pointer; list-style: none; font-weight: 760; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after { content: "+"; position: absolute; right: .35rem; top: 1.05rem; color: var(--teal); font-size: 1.6rem; font-weight: 400; }
.faq-list details[open] summary::after { content: "−"; }
.faq-list details p { margin: -.25rem 2rem 1.35rem 0; color: var(--ink-soft); }
.sources-section { padding: 2.5rem 0; border-top: 1px solid var(--line); background: var(--paper); }
.sources-section h2 { margin-bottom: .4rem; font-size: 1rem; letter-spacing: 0; }
.sources-section p { max-width: 800px; margin: 0; color: var(--ink-soft); font-size: .82rem; }
.sources-section .review-date { margin-top: .45rem; font-size: .75rem; }
.site-footer { padding: 2rem 0; background: #052b37; color: rgba(255,255,255,.7); }
.footer-inner { display: flex; align-items: center; justify-content: space-between; gap: 1.5rem; font-size: .82rem; }
.footer-inner p { margin: 0; }
.footer-brand { color: var(--white); }
.footer-links { display: flex; align-items: center; gap: 1rem; }
.footer-links a, .footer-links button { color: rgba(255,255,255,.76); font: inherit; }
.footer-links button { padding: 0; border: 0; background: none; text-decoration: underline; text-underline-offset: .2em; cursor: pointer; }
.footer-links a:hover, .footer-links button:hover { color: var(--white); }

.consent-banner { position: fixed; z-index: 50; right: 1rem; bottom: 1rem; left: 1rem; display: grid; grid-template-columns: 1fr auto; align-items: center; gap: 2rem; width: min(960px,calc(100% - 2rem)); margin-inline: auto; padding: 1.25rem; border: 1px solid #b8ceca; border-radius: 1rem; background: var(--white); box-shadow: 0 20px 60px rgba(8,45,58,.24); }
.consent-copy h2 { margin: 0 0 .35rem; font-size: 1.15rem; letter-spacing: -.02em; }
.consent-copy p { max-width: 680px; margin: 0 0 .2rem; color: var(--ink-soft); font-size: .88rem; }
.consent-copy a { font-size: .8rem; }
.consent-actions { display: flex; gap: .65rem; }
.consent-button, .inline-settings-button { min-height: 44px; padding: .65rem .9rem; border: 1px solid var(--teal); border-radius: .65rem; font-weight: 760; cursor: pointer; }
.consent-button.secondary { background: var(--white); color: var(--teal-dark); }
.consent-button.primary, .inline-settings-button { background: var(--teal); color: var(--white); }
.consent-button:hover, .inline-settings-button:hover { box-shadow: 0 4px 14px rgba(8,127,117,.18); }
.consent-button:focus-visible, .inline-settings-button:focus-visible, .footer-links button:focus-visible { outline: 3px solid rgba(104,213,189,.5); outline-offset: 3px; }

.legal-page { min-height: calc(100vh - 150px); padding: clamp(4rem,9vw,7rem) 0; background: var(--white); }
.legal-shell { width: min(760px,calc(100% - 2rem)); }
.legal-page h1 { color: var(--ink); }
.legal-lead { margin: 0 0 3rem; color: var(--ink-soft); font-size: 1.15rem; }
.legal-page section { padding: 1.5rem 0; border-top: 1px solid var(--line); }
.legal-page section h2 { font-size: 1.45rem; letter-spacing: -.02em; }
.legal-page section p { color: var(--ink-soft); }
.legal-page code { padding: .1rem .3rem; border-radius: .25rem; background: #eaf2f0; color: var(--ink); }
.inline-settings-button { margin-top: .5rem; }

.not-found { min-height: 100vh; display: grid; place-items: center; padding: 2rem; background: #06313e; color: var(--white); }
.not-found > div { width: min(620px,100%); }
.not-found .brand { margin-bottom: 5rem; }
.not-found h1 { font-size: clamp(2.5rem,8vw,5rem); }
.not-found p:not(.eyebrow) { color: rgba(255,255,255,.72); }
.not-found-link { display: inline-block; margin-top: 1rem; padding: .8rem 1rem; border-radius: .7rem; background: var(--mint-bright); color: var(--ink); font-weight: 800; text-decoration: none; }

@media (max-width: 800px) {
  .site-header nav { display: none; }
  .calculator-section { padding-top: 3rem; background: linear-gradient(180deg,#06313e 0,#06313e 35%,var(--paper) 35%); }
  .calculator-grid { grid-template-columns: 1fr; }
  .result-card { border-left: 0; border-top: 1px solid #cde4de; }
  .section-heading-row, .faq-layout { grid-template-columns: 1fr; gap: 1rem; }
  .faq-intro { position: static; }
  .limitations-grid { grid-template-columns: 1fr; }
}
@media (max-width: 560px) {
  .shell, .narrow-shell { width: min(100% - 1.15rem,1180px); }
  .header-inner { min-height: 64px; }
  .calculator-section { padding-top: 2.4rem; }
  h1 { font-size: 2.65rem; }
  .calculator-card, .result-card { padding: 1.25rem; }
  .field-set:not(.stacked-groups), .formula-grid, .result-summary { grid-template-columns: 1fr; }
  .result-summary { gap: 1rem; }
  .scale-labels { font-size: .58rem; }
  .content-section { padding: 4rem 0; }
  .formula-card { padding: 1.4rem; }
  .footer-inner { flex-direction: column; align-items: flex-start; gap: .7rem; }
  .footer-links { flex-wrap: wrap; }
  .consent-banner { grid-template-columns: 1fr; gap: 1rem; }
  .consent-actions { display: grid; grid-template-columns: 1fr 1fr; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: .01ms !important; animation-duration: .01ms !important; }
}