:root {
      --ink: #171816;
      --ink-soft: #2a2b27;
      --paper: #f7f5ef;
      --white: #fffdf8;
      --line: #d9d5ca;
      --muted: #69695f;
      --orange: #f36b35;
      --orange-dark: #c84418;
      --lime: #c8f06b;
      --cream: #fff0d8;
      --focus: #2563eb;
      --radius: 22px;
      --shadow: 0 24px 70px rgba(23, 24, 22, .12);
    }

    * { box-sizing: border-box; }
    html { scroll-behavior: smooth; }
    body {
      margin: 0;
      color: var(--ink);
      background:
        radial-gradient(circle at 8% 3%, rgba(243, 107, 53, .11), transparent 25rem),
        var(--paper);
      font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
      font-size: 16px;
      line-height: 1.55;
      -webkit-font-smoothing: antialiased;
    }

    button, input, select { font: inherit; }
    button { color: inherit; }
    a { color: inherit; }
    img { display: block; max-width: 100%; }
    .wrap { width: min(1160px, calc(100% - 36px)); margin-inline: auto; }
    .eyebrow {
      margin: 0 0 10px;
      color: var(--orange-dark);
      font-size: .78rem;
      font-weight: 800;
      letter-spacing: .14em;
      text-transform: uppercase;
    }

    .site-header {
      height: 76px;
      display: flex;
      align-items: center;
      border-bottom: 1px solid rgba(23, 24, 22, .09);
      background: rgba(247, 245, 239, .86);
      backdrop-filter: blur(12px);
      position: sticky;
      top: 0;
      z-index: 20;
    }
    .header-inner { display: flex; align-items: center; justify-content: space-between; gap: 24px; }
    .brand { display: inline-flex; align-items: center; gap: 11px; text-decoration: none; font-weight: 850; letter-spacing: -.025em; }
    .brand-mark {
      width: 38px;
      height: 38px;
      border-radius: 12px;
      display: grid;
      place-items: center;
      color: var(--white);
      background: var(--ink);
      box-shadow: inset 0 -3px 0 rgba(255,255,255,.08);
    }
    .brand-mark span { color: var(--orange); font-size: 1.1rem; }
    .nav { display: flex; align-items: center; gap: 26px; }
    .nav a { color: var(--muted); font-size: .9rem; font-weight: 650; text-decoration: none; }
    .nav a:hover, .nav a:focus-visible { color: var(--ink); }

    .intro { padding: 58px 0 28px; }
    .intro-grid { display: grid; grid-template-columns: minmax(0, 1.3fr) minmax(280px, .7fr); align-items: end; gap: 54px; }
    h1, h2, h3 { line-height: 1.08; letter-spacing: -.045em; }
    h1 { margin: 0; max-width: 760px; font-size: clamp(2.65rem, 7vw, 5.6rem); font-weight: 900; }
    h1 em { color: var(--orange); font-style: normal; }
    .intro-copy { margin: 0 0 8px; color: var(--muted); font-size: clamp(1rem, 2vw, 1.18rem); }
    .proof-row { display: flex; flex-wrap: wrap; gap: 12px 20px; margin-top: 22px; color: var(--muted); font-size: .88rem; font-weight: 700; }
    .proof-row span { display: inline-flex; align-items: center; gap: 8px; }
    .proof-row span::before { content: ""; width: 7px; height: 7px; border-radius: 50%; background: var(--orange); }

    .calculator-shell {
      display: grid;
      grid-template-columns: minmax(0, 1.05fr) minmax(360px, .95fr);
      background: var(--white);
      border: 1px solid rgba(23,24,22,.1);
      border-radius: 30px;
      box-shadow: var(--shadow);
      overflow: hidden;
    }
    .calculator-form { padding: clamp(24px, 4vw, 48px); }
    .panel-head { display: flex; align-items: flex-start; justify-content: space-between; gap: 24px; margin-bottom: 30px; }
    .panel-head h2 { margin: 0; font-size: clamp(1.55rem, 3vw, 2.3rem); }
    .unit-switch, .load-switch { display: inline-grid; grid-auto-flow: column; padding: 4px; background: #ebe8df; border-radius: 12px; }
    .unit-switch button, .load-switch label {
      min-width: 52px;
      border: 0;
      border-radius: 9px;
      padding: 8px 12px;
      background: transparent;
      cursor: pointer;
      font-size: .86rem;
      font-weight: 800;
      text-align: center;
    }
    .unit-switch button[aria-pressed="true"], .load-switch label:has(input:checked) { color: var(--white); background: var(--ink); }
    .load-switch input { position: absolute; opacity: 0; pointer-events: none; }
    .field-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
    .field { min-width: 0; }
    .field.full { grid-column: 1 / -1; }
    .field label, .field legend { display: block; margin-bottom: 8px; font-size: .86rem; font-weight: 800; }
    .field legend { padding: 0; }
    .input-wrap { position: relative; }
    input[type="number"], select {
      width: 100%;
      min-height: 52px;
      border: 1px solid var(--line);
      border-radius: 12px;
      padding: 12px 42px 12px 14px;
      color: var(--ink);
      background: #fff;
      outline: none;
    }
    select { appearance: none; background-image: linear-gradient(45deg, transparent 50%, var(--muted) 50%), linear-gradient(135deg, var(--muted) 50%, transparent 50%); background-position: calc(100% - 18px) 22px, calc(100% - 13px) 22px; background-size: 5px 5px; background-repeat: no-repeat; }
    input:focus, select:focus, button:focus-visible, summary:focus-visible, a:focus-visible { outline: 3px solid color-mix(in srgb, var(--focus) 35%, transparent); outline-offset: 2px; }
    .suffix { position: absolute; right: 14px; top: 50%; transform: translateY(-50%); color: var(--muted); font-weight: 800; pointer-events: none; }
    fieldset.field { margin: 0; padding: 0; border: 0; }
    .load-switch { display: grid; grid-template-columns: 1fr 1fr; }
    .load-switch label { min-height: 46px; display: grid; place-items: center; }
    .form-note { margin: 10px 0 0; color: var(--muted); font-size: .82rem; }
    .calculate-button {
      width: 100%;
      min-height: 56px;
      margin-top: 24px;
      border: 0;
      border-radius: 14px;
      color: white;
      background: var(--orange);
      box-shadow: 0 10px 24px rgba(200, 68, 24, .22);
      cursor: pointer;
      font-weight: 850;
      transition: transform .18s ease, background .18s ease;
    }
    .calculate-button:hover { background: var(--orange-dark); transform: translateY(-1px); }

    .result-panel {
      position: relative;
      isolation: isolate;
      min-height: 590px;
      padding: clamp(26px, 4vw, 46px);
      color: var(--white);
      background: var(--ink);
      overflow: hidden;
    }
    .result-panel::after {
      content: "";
      position: absolute;
      inset: auto -120px -150px auto;
      width: 370px;
      aspect-ratio: 1;
      border: 70px solid rgba(243,107,53,.12);
      border-radius: 50%;
      z-index: -1;
    }
    .result-kicker { margin: 0; color: var(--lime); font-size: .77rem; font-weight: 850; letter-spacing: .13em; text-transform: uppercase; }
    .result-title { margin: 11px 0 28px; color: rgba(255,253,248,.72); font-size: 1rem; font-weight: 600; letter-spacing: 0; }
    .setting { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
    .setting-card { padding: 18px 16px; border: 1px solid rgba(255,255,255,.12); border-radius: 17px; background: rgba(255,255,255,.06); }
    .setting-card small { display: block; margin-bottom: 2px; color: rgba(255,255,255,.55); font-size: .78rem; font-weight: 700; }
    .setting-card strong { display: block; font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: clamp(2rem, 5vw, 3.4rem); line-height: 1; letter-spacing: -.08em; }
    .timeline { margin: 28px 0 20px; padding: 18px 0 6px; border-top: 1px solid rgba(255,255,255,.13); }
    .timeline-row { display: grid; grid-template-columns: 72px 1fr; align-items: baseline; gap: 14px; padding: 7px 0; }
    .timeline-row span { color: rgba(255,255,255,.55); font-size: .78rem; font-weight: 800; text-transform: uppercase; }
    .timeline-row b { font-size: .95rem; }
    .safety-note { min-height: 58px; margin: 20px 0; padding: 14px 15px; border-left: 3px solid var(--lime); color: rgba(255,255,255,.8); background: rgba(200,240,107,.07); font-size: .84rem; }
    .result-actions { display: flex; align-items: center; gap: 12px; }
    .copy-button { border: 1px solid rgba(255,255,255,.24); border-radius: 11px; padding: 10px 14px; color: var(--white); background: transparent; cursor: pointer; font-weight: 750; }
    .copy-button:hover { border-color: rgba(255,255,255,.55); }
    .guide-label { color: rgba(255,255,255,.5); font-size: .75rem; }

    .presets { padding: 26px 0 70px; }
    .presets-inner { display: flex; align-items: center; gap: 12px; overflow-x: auto; padding-bottom: 4px; scrollbar-width: thin; }
    .presets strong { flex: 0 0 auto; margin-right: 6px; font-size: .82rem; }
    .preset {
      flex: 0 0 auto;
      border: 1px solid var(--line);
      border-radius: 999px;
      padding: 9px 14px;
      background: transparent;
      cursor: pointer;
      color: var(--muted);
      font-size: .82rem;
      font-weight: 750;
    }
    .preset:hover { color: var(--ink); border-color: var(--ink); }

    .section { padding: 82px 0; }
    .section-dark { color: var(--white); background: var(--ink); }
    .section-head { display: grid; grid-template-columns: .8fr 1.2fr; gap: 54px; align-items: end; margin-bottom: 42px; }
    .section h2 { margin: 0; font-size: clamp(2rem, 5vw, 4.2rem); }
    .section-head p:last-child { margin: 0; color: var(--muted); font-size: 1.04rem; }
    .section-dark .section-head p:last-child { color: rgba(255,255,255,.6); }

    .method-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 24px; }
    .food-photo { min-height: 440px; height: 100%; object-fit: cover; border-radius: var(--radius); }
    .method-card { padding: clamp(24px, 4vw, 42px); border-radius: var(--radius); color: var(--ink); background: var(--cream); }
    .formula { display: grid; grid-template-columns: 1fr auto 1fr; gap: 13px; align-items: center; margin: 24px 0 8px; }
    .formula-box { min-height: 118px; display: grid; place-items: center; border: 1px solid rgba(23,24,22,.15); border-radius: 17px; text-align: center; background: rgba(255,255,255,.44); }
    .formula-box small { display: block; color: var(--muted); font-weight: 700; }
    .formula-box strong { display: block; font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: 1.6rem; }
    .formula-arrow { font-size: 1.5rem; }
    .method-list { margin: 28px 0 0; padding: 0; list-style: none; }
    .method-list li { display: grid; grid-template-columns: 98px 1fr; gap: 12px; padding: 13px 0; border-top: 1px solid rgba(23,24,22,.12); }
    .method-list b { font-size: .85rem; }
    .method-list span { color: var(--muted); font-size: .9rem; }

    .chart-card { overflow: hidden; border: 1px solid var(--line); border-radius: var(--radius); background: var(--white); }
    .chart-toolbar { display: flex; align-items: center; justify-content: space-between; gap: 20px; padding: 18px 22px; border-bottom: 1px solid var(--line); }
    .chart-toolbar p { margin: 0; font-weight: 800; }
    .table-scroll { overflow-x: auto; }
    table { width: 100%; border-collapse: collapse; }
    th, td { padding: 16px 22px; border-bottom: 1px solid #ebe7dc; text-align: left; white-space: nowrap; }
    th { color: var(--muted); background: #fbfaf6; font-size: .76rem; letter-spacing: .07em; text-transform: uppercase; }
    td { font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-weight: 700; }
    tr:last-child td { border-bottom: 0; }
    td:last-child { color: var(--orange-dark); }
    .chart-note { margin: 14px 4px 0; color: var(--muted); font-size: .82rem; }

    .variance-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
    .variance-card { padding: 26px; border: 1px solid rgba(255,255,255,.12); border-radius: 18px; background: rgba(255,255,255,.04); }
    .variance-number { display: grid; place-items: center; width: 38px; height: 38px; margin-bottom: 44px; border-radius: 50%; color: var(--ink); background: var(--lime); font-family: ui-monospace, monospace; font-weight: 900; }
    .variance-card h3 { margin: 0 0 9px; font-size: 1.3rem; letter-spacing: -.025em; }
    .variance-card p { margin: 0; color: rgba(255,255,255,.58); font-size: .9rem; }

    .faq-grid { display: grid; grid-template-columns: .78fr 1.22fr; gap: 64px; }
    .faq-grid h2 { position: sticky; top: 112px; align-self: start; }
    .faq-list { border-top: 1px solid var(--line); }
    details { border-bottom: 1px solid var(--line); }
    summary { position: relative; padding: 24px 44px 24px 0; cursor: pointer; list-style: none; font-weight: 800; }
    summary::-webkit-details-marker { display: none; }
    summary::after { content: "+"; position: absolute; right: 4px; top: 21px; color: var(--orange-dark); font-size: 1.5rem; font-weight: 400; }
    details[open] summary::after { content: "−"; }
    details p { margin: -5px 48px 24px 0; color: var(--muted); }

    .source-card { display: grid; grid-template-columns: 1fr auto; align-items: center; gap: 24px; margin-top: 58px; padding: 24px 26px; border: 1px solid var(--line); border-radius: 18px; background: var(--white); }
    .source-card p { margin: 0; color: var(--muted); }
    .source-card a { color: var(--orange-dark); font-weight: 800; text-decoration-thickness: 1px; text-underline-offset: 3px; }

    .science-section { background: #eef0e8; }
    .science-formulas { display: grid; grid-template-columns: 1.22fr .78fr; gap: 18px; }
    .equation-card { min-height: 280px; display: flex; flex-direction: column; justify-content: space-between; padding: clamp(24px, 4vw, 42px); border: 1px solid rgba(23,24,22,.12); border-radius: var(--radius); background: var(--white); }
    .equation-card-main { color: var(--white); background: var(--ink); }
    .equation-label { color: var(--orange-dark); font-size: .78rem; font-weight: 850; letter-spacing: .12em; text-transform: uppercase; }
    .equation-card-main .equation-label { color: var(--lime); }
    .equation { margin: 34px 0; font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: clamp(1.65rem, 4vw, 3.5rem); font-weight: 850; letter-spacing: -.07em; line-height: 1.1; white-space: nowrap; }
    .equation sub { font-size: .45em; letter-spacing: 0; }
    .equation-card p { margin: 0; color: var(--muted); }
    .equation-card-main p { color: rgba(255,255,255,.66); }
    .equation-card strong { color: inherit; }
    .variable-grid { display: grid; grid-template-columns: repeat(4, 1fr); margin-top: 18px; border: 1px solid var(--line); border-radius: 16px; overflow: hidden; background: rgba(255,255,255,.5); }
    .variable-grid div { display: grid; grid-template-columns: auto 1fr; gap: 12px; align-items: center; padding: 16px; border-right: 1px solid var(--line); }
    .variable-grid div:last-child { border-right: 0; }
    .variable-grid b { display: grid; place-items: center; width: 34px; height: 34px; border-radius: 9px; color: var(--white); background: var(--orange-dark); font-family: ui-monospace, monospace; }
    .variable-grid span { color: var(--muted); font-size: .78rem; line-height: 1.35; }
    .science-copy-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 34px; margin-top: 62px; }
    .science-copy-grid article { padding-top: 18px; border-top: 2px solid var(--ink); }
    .science-copy-grid h3 { margin: 24px 0 10px; font-size: 1.45rem; }
    .science-copy-grid p { margin: 0; color: var(--muted); }
    .science-index { color: var(--orange-dark); font-family: ui-monospace, monospace; font-weight: 900; }

    .evidence-section { background: var(--white); }
    .evidence-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
    .evidence-card { display: flex; flex-direction: column; min-height: 490px; padding: 28px; border: 1px solid var(--line); border-radius: 19px; background: var(--paper); }
    .evidence-card-accent { color: var(--white); border-color: var(--ink); background: var(--ink); }
    .evidence-meta { display: flex; justify-content: space-between; gap: 12px; margin-bottom: 52px; color: var(--muted); font-size: .72rem; font-weight: 850; letter-spacing: .08em; text-transform: uppercase; }
    .evidence-card-accent .evidence-meta { color: rgba(255,255,255,.55); }
    .evidence-card h3 { margin: 0 0 18px; font-size: 1.55rem; }
    .evidence-card p { margin: 0 0 16px; color: var(--muted); font-size: .91rem; }
    .evidence-card-accent p { color: rgba(255,255,255,.67); }
    .evidence-card .evidence-limit { margin-top: auto; padding-top: 18px; border-top: 1px solid var(--line); }
    .evidence-card-accent .evidence-limit { border-color: rgba(255,255,255,.15); }
    .evidence-card a { margin-top: 18px; color: var(--orange-dark); font-size: .84rem; font-weight: 850; text-underline-offset: 3px; }
    .evidence-card-accent a { color: var(--lime); }
    .evidence-links { display: flex; gap: 18px; }
    .temperature-list { margin: 8px 0 18px; padding: 0; list-style: none; }
    .temperature-list li { display: flex; justify-content: space-between; gap: 16px; padding: 10px 0; border-bottom: 1px solid rgba(255,255,255,.13); font-size: .83rem; }
    .temperature-list span { color: rgba(255,255,255,.58); }
    .evidence-card small { color: rgba(255,255,255,.5); font-size: .72rem; }

    .calibration-section { background: var(--cream); }
    .calibration-grid { display: grid; grid-template-columns: .82fr 1.18fr; gap: clamp(40px, 8vw, 110px); align-items: start; }
    .calibration-grid h2 { max-width: 620px; }
    .calibration-lead { max-width: 560px; margin: 24px 0 0; color: var(--muted); font-size: 1.05rem; }
    .calibration-steps { margin: 0; padding: 0; list-style: none; counter-reset: steps; }
    .calibration-steps li { display: grid; grid-template-columns: 48px 1fr; gap: 20px; padding: 22px 0; border-bottom: 1px solid rgba(23,24,22,.15); }
    .calibration-steps li:first-child { padding-top: 0; }
    .calibration-steps li > span { display: grid; place-items: center; width: 42px; height: 42px; border-radius: 50%; color: var(--white); background: var(--orange-dark); font-family: ui-monospace, monospace; font-weight: 900; }
    .calibration-steps h3 { margin: 2px 0 7px; font-size: 1.18rem; letter-spacing: -.02em; }
    .calibration-steps p { margin: 0; color: var(--muted); font-size: .9rem; }

    .video-section { color: var(--white); background: #20211e; }
    .video-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
    .video-card { overflow: hidden; border: 1px solid rgba(255,255,255,.13); border-radius: var(--radius); color: inherit; background: rgba(255,255,255,.045); text-decoration: none; transition: transform .2s ease, border-color .2s ease; }
    .video-card:hover { transform: translateY(-3px); border-color: rgba(255,255,255,.35); }
    .video-image { position: relative; aspect-ratio: 16 / 9; overflow: hidden; background: #111; }
    .video-image img { width: 100%; height: 100%; object-fit: cover; opacity: .83; transition: transform .35s ease, opacity .2s ease; }
    .video-card:hover img { transform: scale(1.025); opacity: 1; }
    .play-button { position: absolute; inset: 50% auto auto 50%; transform: translate(-50%, -50%); display: grid; place-items: center; width: 64px; height: 64px; padding-left: 4px; border-radius: 50%; color: var(--white); background: var(--orange); box-shadow: 0 12px 28px rgba(0,0,0,.35); }
    .video-copy { padding: 25px 26px 28px; }
    .video-copy span { color: var(--lime); font-size: .73rem; font-weight: 850; letter-spacing: .1em; text-transform: uppercase; }
    .video-copy h3 { margin: 12px 0 22px; font-size: 1.35rem; }
    .video-copy p { margin: 0; color: rgba(255,255,255,.57); font-size: .82rem; font-weight: 750; }
    .video-disclaimer { max-width: 760px; margin: 22px 0 0; color: rgba(255,255,255,.47); font-size: .8rem; }

    footer { padding: 34px 0; border-top: 1px solid var(--line); color: var(--muted); }
    .footer-inner { display: flex; justify-content: space-between; gap: 24px; font-size: .82rem; }
    .footer-inner a { text-underline-offset: 3px; }

    .toast { position: fixed; right: 22px; bottom: 22px; z-index: 30; padding: 11px 15px; border-radius: 10px; color: white; background: var(--ink); box-shadow: var(--shadow); font-size: .86rem; font-weight: 750; transform: translateY(20px); opacity: 0; pointer-events: none; transition: .2s ease; }
    .toast.show { transform: translateY(0); opacity: 1; }

    @media (max-width: 900px) {
      .intro-grid, .section-head, .method-grid, .faq-grid, .science-formulas, .calibration-grid { grid-template-columns: 1fr; gap: 24px; }
      .calculator-shell { grid-template-columns: 1fr; }
      .result-panel { min-height: 0; }
      .variance-grid, .evidence-grid { grid-template-columns: 1fr; }
      .science-copy-grid { grid-template-columns: 1fr; }
      .variable-grid { grid-template-columns: 1fr 1fr; }
      .variable-grid div:nth-child(2) { border-right: 0; }
      .variable-grid div:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
      .evidence-card { min-height: 0; }
      .variance-number { margin-bottom: 20px; }
      .faq-grid h2 { position: static; }
      .food-photo { min-height: 340px; }
    }

    @media (max-width: 650px) {
      .wrap { width: min(100% - 24px, 1160px); }
      .site-header { height: 66px; }
      .nav { display: none; }
      .intro { padding-top: 38px; }
      .calculator-shell { border-radius: 22px; }
      .panel-head { align-items: center; }
      .field-grid { grid-template-columns: 1fr; }
      .field.full { grid-column: auto; }
      .setting-card strong { font-size: 2.15rem; }
      .section { padding: 64px 0; }
      .formula { grid-template-columns: 1fr; }
      .formula-arrow { transform: rotate(90deg); text-align: center; }
      .method-list li { grid-template-columns: 1fr; gap: 3px; }
      .equation { white-space: normal; font-size: 1.45rem; }
      .variable-grid, .video-grid { grid-template-columns: 1fr; }
      .variable-grid div { border-right: 0; border-bottom: 1px solid var(--line); }
      .variable-grid div:last-child { border-bottom: 0; }
      .chart-toolbar, .source-card, .footer-inner { align-items: flex-start; flex-direction: column; grid-template-columns: 1fr; }
      th, td { padding: 14px 16px; }
    }

    @media (prefers-reduced-motion: reduce) {
      html { scroll-behavior: auto; }
      *, *::before, *::after { transition-duration: .01ms !important; }
    }