:root {
    --calc-navy: #061421;
    --calc-panel: rgba(13, 35, 52, .88);
    --calc-cyan: #3de1d0;
    --calc-cyan-soft: rgba(61, 225, 208, .14);
    --calc-blue: #59a9ff;
    --calc-white: #f4fbff;
    --calc-muted: #a9bdca;
    --calc-line: rgba(197, 229, 244, .17);
    --calc-warn: #ffb454;
    --calc-danger: #ff7185;
}
* { box-sizing: border-box; }
body.calculator-page {
    margin: 0; min-height: 100vh; color: var(--calc-white);
    background:
        radial-gradient(circle at 15% 10%, rgba(24, 120, 142, .28), transparent 34rem),
        radial-gradient(circle at 90% 80%, rgba(41, 87, 151, .22), transparent 38rem),
        var(--calc-navy);
}
.calculator-shell { width: min(1120px, calc(100% - 32px)); margin: 0 auto; padding: 48px 0 64px; }
.calculator-intro { margin-bottom: 28px; }
.calculator-eyebrow {
    display: inline-flex; align-items: center; gap: 8px; color: var(--calc-cyan);
    font-size: .78rem; font-weight: 800; letter-spacing: .14em; text-transform: uppercase;
}
.calculator-eyebrow::before { content: ""; width: 28px; height: 2px; background: currentColor; }
.calculator-intro h1 { margin: 8px 0 6px; font-size: clamp(2rem, 5vw, 3.5rem); line-height: 1.08; letter-spacing: -.045em; }
.calculator-lead { margin: 0; max-width: 790px; color: var(--calc-muted); font-size: 1.05rem; }
.calculator-grid { display: grid; grid-template-columns: minmax(300px, .85fr) minmax(390px, 1.15fr); gap: 24px; align-items: start; }
.calculator-card {
    padding: 28px; border: 1px solid var(--calc-line); border-radius: 24px;
    background: var(--calc-panel); box-shadow: 0 24px 70px rgba(0,0,0,.3); backdrop-filter: blur(16px);
}
.calculator-card h2 { margin: 0 0 5px; font-size: 1.2rem; }
.calculator-subtitle { margin: 0 0 22px; color: var(--calc-muted); font-size: .9rem; }
.calculator-fields { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.calculator-field--wide { grid-column: 1 / -1; }
.calculator-field label { display: flex; justify-content: space-between; gap: 10px; margin-bottom: 7px; color: #d7e8f1; font-size: .88rem; font-weight: 700; }
.calculator-field output { color: var(--calc-cyan); }
.calculator-input-wrap { position: relative; }
.calculator-field input[type="number"] {
    width: 100%; min-height: 52px; padding: 11px 58px 11px 14px; color: var(--calc-white);
    border: 1px solid var(--calc-line); border-radius: 12px; outline: none;
    background: rgba(3,16,26,.58); font: inherit; font-size: 1.04rem;
}
.calculator-field input[type="range"] { width: 100%; accent-color: var(--calc-cyan); }
.calculator-field input:focus { border-color: var(--calc-cyan); box-shadow: 0 0 0 3px var(--calc-cyan-soft); }
.calculator-unit { position: absolute; right: 14px; top: 50%; transform: translateY(-50%); color: var(--calc-muted); font-weight: 700; }
.calculator-presets { display: flex; flex-wrap: wrap; gap: 8px; margin: 18px 0 0; }
.calculator-presets button {
    padding: 8px 12px; color: var(--calc-white); border: 1px solid var(--calc-line);
    border-radius: 999px; background: rgba(3,16,26,.5); font: inherit; font-size: .82rem; cursor: pointer;
}
.calculator-presets button:hover, .calculator-presets button:focus-visible { border-color: var(--calc-cyan); }
.calculator-stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; margin-top: 22px; }
.calculator-stat { min-width: 0; padding: 14px; border-radius: 14px; background: rgba(2,16,26,.46); }
.calculator-stat span { display: block; color: var(--calc-muted); font-size: .75rem; }
.calculator-stat strong { display: block; margin-top: 3px; font-size: clamp(1.18rem, 3vw, 1.7rem); line-height: 1.15; }
.calculator-stat strong.is-ppo2-warning { color: var(--calc-warn); }
.calculator-stat strong.is-ppo2-danger { color: var(--calc-danger); }
.calculator-stat small { color: var(--calc-muted); }
.calculator-meter { margin-top: 24px; }
.calculator-meter-head { display: flex; justify-content: space-between; gap: 15px; margin-bottom: 8px; font-size: .88rem; }
.calculator-track { position: relative; height: 18px; overflow: hidden; border-radius: 99px; background: rgba(255,255,255,.09); }
.calculator-fill { height: 100%; width: 0; border-radius: inherit; background: linear-gradient(90deg, var(--calc-cyan), var(--calc-blue)); transition: width .35s ease; }
.calculator-fill.is-warning { background: linear-gradient(90deg, var(--calc-cyan), var(--calc-warn)); }
.calculator-fill.is-danger { background: linear-gradient(90deg, var(--calc-warn), var(--calc-danger)); }
.calculator-marker { position: absolute; top: -3px; bottom: -3px; left: 100%; width: 2px; background: var(--calc-white); }
.calculator-status { margin: 12px 0 0; color: var(--calc-muted); font-size: .88rem; }
.calculator-status strong { color: var(--calc-white); }
.calculator-visual { min-height: 410px; }
.clock { position: relative; width: min(310px, 80vw); aspect-ratio: 1; margin: 18px auto 20px; border-radius: 50%; background: conic-gradient(var(--calc-cyan) 0deg, rgba(255,255,255,.08) 0); box-shadow: 0 0 35px rgba(61,225,208,.12); }
.clock::before { content: ""; position: absolute; inset: 18px; border-radius: 50%; background: #0b2233; border: 1px solid var(--calc-line); }
.clock-center { position: absolute; z-index: 1; inset: 0; display: grid; place-content: center; text-align: center; }
.clock-center strong { font-size: clamp(2.2rem, 8vw, 3.8rem); line-height: 1; }
.clock-center span { margin-top: 8px; color: var(--calc-muted); font-size: .85rem; }
.depth-visual { position: relative; height: 330px; margin-top: 22px; overflow: hidden; border-radius: 18px; background: linear-gradient(#1779a3, #073550 72%, #082638); }
.depth-surface { position: absolute; inset: 20px 0 auto; height: 2px; background: rgba(255,255,255,.65); }
.depth-line { position: absolute; top: 21px; bottom: 24px; width: 2px; }
.depth-line span { position: absolute; left: 9px; transform: translateY(-50%); white-space: nowrap; font-size: .8rem; font-weight: 700; }
.depth-line--real { left: 35%; background: var(--calc-white); }
.depth-line--ead { left: 68%; background: var(--calc-cyan); }
.depth-diver { position: absolute; left: 50%; transform: translate(-50%, -50%); font-size: 2rem; transition: top .35s ease; }
.depth-scale { position: absolute; inset: 20px auto 24px 12px; display: flex; flex-direction: column; justify-content: space-between; color: rgba(255,255,255,.68); font-size: .72rem; }
.calculator-table-wrap { margin-top: 24px; overflow-x: auto; }
.calculator-table { width: 100%; border-collapse: collapse; font-size: .82rem; }
.calculator-table th, .calculator-table td { padding: 8px 9px; text-align: right; border-bottom: 1px solid var(--calc-line); white-space: nowrap; }
.calculator-table th:first-child, .calculator-table td:first-child { text-align: left; }
.calculator-table tr.is-active { background: var(--calc-cyan-soft); }
.calculator-info { margin-top: 24px; padding: 22px 24px; border: 1px solid var(--calc-line); border-radius: 20px; background: rgba(9,29,43,.66); }
.calculator-info h2 { margin: 0 0 8px; font-size: 1.15rem; }
.calculator-info p { margin: 8px 0 0; color: var(--calc-muted); }
.calculator-links { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 16px; }
.calculator-links a { color: var(--calc-cyan); }
.calculator-reference { margin-top: 24px; }
.calculator-reference-head { display: flex; align-items: end; justify-content: space-between; gap: 18px; margin-bottom: 14px; }
.calculator-reference-head h2 { margin: 0; font-size: 1.2rem; }
.calculator-reference-head p { margin: 4px 0 0; color: var(--calc-muted); font-size: .88rem; }
.calculator-reference-head a { flex: 0 0 auto; color: var(--calc-cyan); }
.calculator-pdf {
    display: block; width: 100%; height: min(72vw, 780px); min-height: 440px;
    border: 1px solid var(--calc-line); border-radius: 18px; background: #fff;
}
.calculator-pdf-fallback { padding: 28px; color: #102b3f; background: #fff; }
.calculator-pdf-fallback a { color: #075b73; font-weight: 700; }
@media (max-width: 820px) {
    .calculator-shell { padding-top: 28px; }
    .calculator-grid { grid-template-columns: 1fr; }
}
@media (max-width: 520px) {
    .calculator-shell { width: min(100% - 20px, 1120px); }
    .calculator-card { padding: 20px; }
    .calculator-fields, .calculator-stats { grid-template-columns: 1fr; }
    .calculator-field--wide { grid-column: auto; }
    .calculator-reference-head { align-items: start; flex-direction: column; }
    .calculator-pdf { height: 72vh; min-height: 480px; }
}
@media (prefers-reduced-motion: reduce) {
    .calculator-fill, .depth-diver { transition: none; }
}