:root {
  --canvas: #0d0f0e;
  --surface: #161918;
  --ink: #ece8e1;
  --ink-soft: #a3aaa4;
  --ink-mute: #6f7771;
  --accent: #ff6a2b;
  --accent-ink: #170b05;
  --ok: #8fc79a;
  --bad: #ff7a5c;
  --line: rgba(169, 193, 207, 0.16);
  --glass: rgba(18, 21, 20, 0.58);
  --glass-edge: rgba(236, 232, 225, 0.09);

  --f-display: "Archivo", system-ui, sans-serif;
  --f-mono: "IBM Plex Mono", ui-monospace, monospace;

  --s1: 4px; --s2: 8px; --s3: 12px; --s4: 16px; --s5: 24px; --s6: 32px; --s7: 48px; --s8: 64px; --s9: 96px; --s10: 128px;
  --gutter: clamp(16px, 4vw, 64px);
  --ease: cubic-bezier(.2, .7, .1, 1);
  color-scheme: dark;
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
html.lenis, html.lenis body { height: auto; }
.lenis.lenis-smooth { scroll-behavior: auto !important; }
body {
  margin: 0; background: var(--canvas); color: var(--ink);
  font-family: var(--f-display); font-stretch: 100%; font-weight: 400;
  font-size: 17px; line-height: 1.62; letter-spacing: 0.005em;
  -webkit-font-smoothing: antialiased; overflow-x: hidden;
}
a { color: inherit; }
.mono { font-family: var(--f-mono); font-size: 0.78rem; letter-spacing: 0.02em; }
p { text-wrap: pretty; max-width: 62ch; margin: 0 0 var(--s4); }
h1, h2, h3, h4 { text-wrap: balance; margin: 0; }

/* ---------- stage ---------- */
#world { position: fixed; inset: 0; width: 100%; height: 100%; display: block; z-index: 0; }
.grain {
  position: fixed; inset: -50%; z-index: 1; pointer-events: none; opacity: .07;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}
main { position: relative; z-index: 2; }
.no-webgl #world { display: none; }
.no-webgl { background: radial-gradient(120% 80% at 70% 30%, #1d211f, var(--canvas) 70%) fixed; }

/* ---------- loader ---------- */
.loader { position: fixed; inset: 0; z-index: 50; background: var(--canvas); display: grid; place-content: center; gap: var(--s4); text-align: center; transition: opacity 1.1s var(--ease), visibility 1.1s; }
.loader.is-done { opacity: 0; visibility: hidden; }
.loader__mark { font-weight: 800; font-stretch: 125%; font-size: 1.4rem; letter-spacing: -0.01em; }
.loader__line { width: 220px; height: 1px; background: var(--line); overflow: hidden; }
.loader__line span { display: block; height: 100%; width: 100%; background: var(--accent); transform-origin: left; transform: scaleX(0); transition: transform .5s var(--ease); }
.loader__note { color: var(--ink-mute); }

/* ---------- chrome ---------- */
.top { position: fixed; top: 0; left: 0; right: 0; z-index: 20; display: flex; justify-content: space-between; align-items: center; padding: var(--s5) var(--gutter); pointer-events: none; }
.top > * { pointer-events: auto; }
.top::before { content: ""; position: absolute; inset: 0 0 -40px; z-index: -1; background: linear-gradient(to bottom, rgba(13,15,14,.92), rgba(13,15,14,.6) 55%, transparent); opacity: 0; transition: opacity .5s; }
.top.is-scrolled::before { opacity: 1; }
.wordmark { font-stretch: 125%; font-weight: 500; text-decoration: none; font-size: 1.05rem; letter-spacing: -0.01em; }
.wordmark b { font-weight: 800; }
.top__cta { font-family: var(--f-mono); font-size: .78rem; text-decoration: none; padding: 10px 16px; border: 1px solid var(--glass-edge); border-radius: 999px; background: var(--glass); backdrop-filter: blur(14px); -webkit-backdrop-filter: blur(14px); transition: background .3s, color .3s, border-color .3s; }
.top__cta:hover, .top__cta:focus-visible { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); }

/* level rail: section stops drawn as floor levels on a building section */
.rail { display: none; position: fixed; right: var(--gutter); top: 50%; transform: translateY(-50%); z-index: 20; }
.rail ol { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column-reverse; gap: 10px; border-right: 1px solid var(--line); padding-right: 14px; }
.rail a { display: flex; align-items: center; justify-content: flex-end; gap: 10px; text-decoration: none; color: var(--ink-mute); font-family: var(--f-mono); font-size: .68rem; min-height: 18px; }
.rail a .lv { opacity: 0; transform: translateX(6px); transition: opacity .3s, transform .4s var(--ease); white-space: nowrap; }
.rail a .tick { width: 14px; height: 1px; background: currentColor; transition: width .4s var(--ease), background .3s; }
.rail a:hover .lv, .rail a:focus-visible .lv { opacity: 1; transform: none; }
.rail a.is-on { color: var(--ink); }
.rail a.is-on .tick { width: 28px; background: var(--accent); }

/* labels pinned to 3D silos */
.labels { position: fixed; inset: 0; z-index: 3; pointer-events: none; transition: opacity .6s; opacity: 0; }
.labels.is-on { opacity: 1; }
.labels div { position: absolute; left: 0; top: 0; font-family: var(--f-mono); font-size: .68rem; color: var(--ink); white-space: nowrap; transform: translate(-50%, -100%); padding-bottom: 6px; border-bottom: 1px solid var(--accent); line-height: 1.3; text-align: center; will-change: transform; }
.labels div small { display: block; color: var(--ink-soft); }

/* ---------- type ---------- */
.display { font-size: clamp(3rem, 7.4vw, 7.2rem); font-weight: 760; font-stretch: 112%; line-height: .94; letter-spacing: -0.035em; }
.display em { font-style: italic; color: var(--accent); font-weight: 760; }
.h2 { font-size: clamp(2rem, 3.8vw, 3.6rem); font-weight: 700; font-stretch: 108%; line-height: 1.02; letter-spacing: -0.025em; margin-bottom: var(--s5); }
.h3 { font-size: 1.5rem; font-weight: 700; font-stretch: 108%; letter-spacing: -0.015em; line-height: 1.1; }
.h4 { font-size: 1.05rem; font-weight: 700; font-stretch: 105%; letter-spacing: -0.005em; margin-bottom: var(--s2); }
.eyebrow { color: var(--accent); margin: 0 0 var(--s5); text-transform: uppercase; letter-spacing: .14em; font-size: .72rem; }
.lede { font-size: 1.16rem; color: var(--ink); max-width: 46ch; margin-top: var(--s6); }
.sub { color: var(--ink-soft); font-size: .86rem; margin: 0 0 var(--s4); line-height: 1.5; }
.note { color: var(--ink-soft); margin-top: var(--s4); }

/* ---------- acts ---------- */
.act { position: relative; min-height: 100vh; padding: var(--s10) var(--gutter); display: flex; }
.act--hero { min-height: 100vh; align-items: flex-end; padding-bottom: 14vh; }
.act--pour { min-height: 150vh; align-items: center; }
.act--problem { min-height: 170vh; flex-direction: column; justify-content: center; gap: var(--s6); }
.act--objectives { min-height: 140vh; align-items: center; }
.act--data { min-height: 150vh; align-items: center; }
.act--model { min-height: 160vh; flex-direction: column; justify-content: center; gap: var(--s7); }
.act--lab { min-height: 100vh; padding-top: var(--s9); padding-bottom: var(--s7); }
.act--analysis { min-height: 140vh; }
.act--green { min-height: 140vh; }
.act--close { min-height: 120vh; align-items: center; }

.copy { position: relative; max-width: 560px; }
.copy--lead { margin-right: auto; }
.copy--trail { margin-left: auto; margin-right: clamp(64px, 9vw, 150px); }
.copy--split { max-width: 1040px; width: 100%; display: grid; grid-template-columns: 1fr 1.25fr; gap: var(--s8); align-items: start; margin-left: auto; margin-right: clamp(64px, 9vw, 150px); }
.copy p { color: var(--ink); }
/* readable ground under copy: a soft column, not a full-frame overlay */
.copy::before { content: ""; position: absolute; inset: -18% -30% -18% -40%; z-index: -1; pointer-events: none;
  background: radial-gradient(closest-side, rgba(13,15,14,.82), rgba(13,15,14,.55) 55%, transparent); }
.act--hero .copy::before { inset: -30% -40% -30% -50%; }

.hero__meta { position: absolute; right: clamp(80px, 9vw, 160px); bottom: 14vh; display: flex; flex-direction: column; gap: 6px; color: var(--ink-soft); text-align: right; }

.facts { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--s5); width: min(640px, 100%); margin-right: auto; padding: var(--s5) var(--s6); background: var(--glass); border: 1px solid var(--glass-edge); border-radius: 14px; backdrop-filter: blur(18px); -webkit-backdrop-filter: blur(18px); }
.fact { display: flex; flex-direction: column; gap: var(--s2); border-top: 1px solid var(--accent); padding-top: var(--s4); }
.fact__n { font-size: 2.6rem; font-weight: 760; font-stretch: 112%; letter-spacing: -0.03em; line-height: 1; }
.fact__n small { font-size: .9rem; font-weight: 500; margin-left: 6px; color: var(--ink-soft); letter-spacing: 0; }
.fact__t { color: var(--ink-soft); font-size: .86rem; line-height: 1.45; }

.objectives { list-style: none; margin: 0; padding: 0; counter-reset: o; display: grid; gap: 2px; }
.objectives li { display: grid; grid-template-columns: 140px 1fr; gap: var(--s5); padding: var(--s5) var(--s5); background: var(--glass); backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px); border-left: 2px solid transparent; transition: border-color .4s, transform .5s var(--ease); }
.objectives li:hover { border-left-color: var(--accent); transform: translateX(-6px); }
.objectives b { font-stretch: 115%; font-size: 1.15rem; font-weight: 700; }
.objectives span { color: var(--ink-soft); line-height: 1.5; }

/* ---------- panels (glass) ---------- */
.panel { background: var(--glass); border: 1px solid var(--glass-edge); border-radius: 14px; backdrop-filter: blur(18px) saturate(1.1); -webkit-backdrop-filter: blur(18px) saturate(1.1); box-shadow: 0 30px 60px -30px rgba(0,0,0,.6); }

/* data table */
.table-wrap { margin-top: var(--s5); }
.datatable { width: 100%; border-collapse: collapse; font-size: .84rem; }
.datatable th { text-align: left; font-family: var(--f-mono); font-weight: 400; font-size: .7rem; color: var(--ink-mute); padding: 0 var(--s3) var(--s2) 0; border-bottom: 1px solid var(--line); }
.datatable td { padding: 7px var(--s3) 7px 0; border-bottom: 1px solid rgba(169,193,207,.07); vertical-align: middle; }
.datatable td:nth-child(2), .datatable td:nth-child(3) { font-family: var(--f-mono); font-size: .74rem; color: var(--ink-soft); white-space: nowrap; }
.datatable tr:hover td { color: var(--ink); }
.datatable tr:last-child td:first-child { color: var(--accent); }
.spark { display: block; width: 120px; height: 26px; }
.spark rect { fill: var(--ink-soft); }
.datatable tr:hover .spark rect { fill: var(--accent); }

/* model */
.metrics { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--s5); margin-top: var(--s6); }
.metric { border-top: 1px solid var(--line); padding-top: var(--s3); }
.metric b { display: block; font-size: 2.2rem; font-stretch: 112%; font-weight: 740; letter-spacing: -0.03em; line-height: 1.05; }
.metric span { font-family: var(--f-mono); font-size: .7rem; color: var(--ink-soft); }
.metric em { font-style: normal; color: var(--ink-mute); }
.model-charts { display: grid; grid-template-columns: 1.15fr 1fr; gap: var(--s5); width: min(900px, 62vw); margin-right: auto; }

.chart { margin: 0; padding: var(--s5); position: relative; }
.chart figcaption { display: flex; flex-direction: column; gap: 2px; margin-bottom: var(--s4); }
.chart figcaption b { font-weight: 700; font-stretch: 105%; }
.chart figcaption span { color: var(--ink-soft); font-size: .8rem; }
.chart svg { display: block; width: 100%; height: auto; overflow: visible; }
.axis text, .lbl { font-family: var(--f-mono); font-size: 10px; fill: var(--ink-soft); }
.axis line, .axis path { stroke: var(--line); }
.grid line { stroke: rgba(169,193,207,.08); }
.tip { position: absolute; pointer-events: none; background: #0b0d0c; border: 1px solid var(--glass-edge); padding: 6px 9px; border-radius: 8px; font-family: var(--f-mono); font-size: .72rem; color: var(--ink); white-space: nowrap; opacity: 0; transform: translate(-50%, calc(-100% - 10px)); transition: opacity .15s; z-index: 5; }
.tip.is-on { opacity: 1; }

/* ---------- lab ---------- */
.lab { width: 100%; display: grid; grid-template-columns: minmax(320px, 400px) 1fr minmax(230px, 280px); gap: var(--s5); align-items: start; }
.lab__controls { grid-column: 1; padding: var(--s5); max-height: calc(100vh - 130px); max-height: calc(100dvh - 130px); overflow-y: auto; overscroll-behavior: contain; scrollbar-width: thin; scrollbar-color: rgba(236,232,225,.25) transparent; }
.lab__head { margin-bottom: var(--s4); }
.lab__head .sub { margin-top: var(--s2); }
.presets { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: var(--s5); }
.chip { font-family: var(--f-mono); font-size: .72rem; padding: 8px 12px; border-radius: 999px; border: 1px solid var(--glass-edge); background: rgba(236,232,225,.04); color: var(--ink); cursor: pointer; transition: background .25s, border-color .25s, color .25s; }
.chip:hover { border-color: var(--ink-soft); }
.chip[aria-pressed="true"] { background: var(--ink); color: var(--canvas); border-color: var(--ink); }

.slider { display: grid; grid-template-columns: 1fr auto; align-items: baseline; gap: 2px var(--s3); padding: 9px 0; border-bottom: 1px solid rgba(169,193,207,.07); }
.slider label { font-size: .88rem; }
.slider output { font-family: var(--f-mono); font-size: .8rem; color: var(--ink); }
.slider output small { color: var(--ink-mute); }
.slider input { grid-column: 1 / -1; }
input[type=range] { -webkit-appearance: none; appearance: none; width: 100%; height: 22px; background: transparent; cursor: pointer; margin: 0; }
input[type=range]::-webkit-slider-runnable-track { height: 2px; background: linear-gradient(to right, var(--accent) var(--fill, 50%), rgba(236,232,225,.16) var(--fill, 50%)); }
input[type=range]::-moz-range-track { height: 2px; background: rgba(236,232,225,.16); }
input[type=range]::-moz-range-progress { height: 2px; background: var(--accent); }
input[type=range]::-webkit-slider-thumb { -webkit-appearance: none; width: 16px; height: 16px; margin-top: -7px; border-radius: 3px; background: var(--ink); border: 3px solid var(--canvas); box-shadow: 0 0 0 1px var(--ink-soft); transition: transform .2s; }
input[type=range]::-moz-range-thumb { width: 12px; height: 12px; border-radius: 3px; background: var(--ink); border: 3px solid var(--canvas); }
input[type=range]:active::-webkit-slider-thumb { transform: scale(1.2); }
input[type=range]:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }
.lab__row { display: grid; grid-template-columns: 1fr 1fr; gap: var(--s3); margin-top: var(--s5); }
.field { display: flex; flex-direction: column; gap: 6px; font-size: .78rem; color: var(--ink-soft); }
select { font: inherit; font-family: var(--f-mono); font-size: .78rem; color: var(--ink); background: rgba(236,232,225,.05); border: 1px solid var(--glass-edge); border-radius: 8px; padding: 9px 10px; }
select:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

.readout { grid-column: 3; padding: var(--s5); display: grid; grid-template-columns: 1fr; gap: var(--s5); }
.readout__main { display: flex; flex-direction: column; }
.readout__label { color: var(--ink-soft); }
.readout__num { font-size: clamp(3rem, 4.6vw, 4.4rem); font-weight: 780; font-stretch: 118%; letter-spacing: -0.04em; line-height: .95; font-variant-numeric: tabular-nums; }
.readout__num small { font-size: 1rem; font-weight: 500; letter-spacing: 0; margin-left: 8px; color: var(--ink-soft); }
.readout__band { color: var(--accent); margin-top: 6px; }
.readout__grid { display: grid; grid-template-columns: 1fr 1fr; gap: var(--s4) var(--s5); }
.readout__grid span { display: block; color: var(--ink-mute); font-size: .68rem; }
.readout__grid b { font-size: 1.2rem; font-stretch: 112%; font-weight: 700; font-variant-numeric: tabular-nums; }
.readout__grid b small { font-size: .7rem; font-weight: 400; color: var(--ink-soft); }
.readout__warn { grid-column: 1 / -1; margin: 0; font-size: .8rem; color: var(--bad); border-top: 1px solid rgba(255,122,92,.3); padding-top: var(--s3); }
.bump { animation: bump .5s var(--ease); }
@keyframes bump { 30% { transform: translateY(-3px); color: var(--accent); } }

/* ---------- analysis ---------- */
.analysis { width: 100%; max-width: 1180px; margin: 0 auto; padding-top: 10vh; }
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--s5); }
.card { padding: var(--s5); }
.card--wide { grid-column: span 2; }
.checks { width: 100%; border-collapse: collapse; font-size: .84rem; }
.checks td { padding: 9px 0; border-bottom: 1px solid rgba(169,193,207,.08); }
.checks td:nth-child(2), .checks td:nth-child(3) { font-family: var(--f-mono); font-size: .74rem; color: var(--ink-soft); text-align: right; padding-left: 10px; }
.checks td:nth-child(3) { color: var(--ink); }
.pass, .fail { font-family: var(--f-mono); font-size: .68rem; padding: 2px 7px; border-radius: 4px; margin-left: 8px; }
.pass { background: rgba(143,199,154,.14); color: var(--ok); }
.fail { background: rgba(255,122,92,.14); color: var(--bad); }
.colcalc { display: grid; gap: var(--s3); }
.colcalc .row { display: flex; justify-content: space-between; font-family: var(--f-mono); font-size: .78rem; color: var(--ink-soft); border-bottom: 1px solid rgba(169,193,207,.08); padding-bottom: 8px; }
.colcalc .row b { color: var(--ink); font-weight: 500; }
.colcalc .big { font-size: 2.4rem; font-weight: 760; font-stretch: 115%; letter-spacing: -0.03em; line-height: 1; }
.colcalc .big small { font-size: .85rem; color: var(--ink-soft); font-weight: 400; letter-spacing: 0; margin-left: 6px; }
.interp p { color: var(--ink); max-width: 80ch; }
.interp p b { color: var(--accent); font-weight: 600; }

/* ---------- green ---------- */
.green { width: 100%; display: grid; grid-template-columns: minmax(300px, 0.85fr) 1.3fr; grid-template-rows: auto 1fr; gap: var(--s5) var(--s7); align-items: start; max-width: 1240px; margin: 0 auto; padding-top: 6vh; }
.green__result { grid-column: 1; }
.copy--flow { max-width: 460px; }
.green__plot { grid-column: 2; grid-row: 1 / span 2; }
.green__plot canvas { width: 100%; height: auto; display: block; }
.legend { display: flex; flex-wrap: wrap; gap: var(--s4); color: var(--ink-soft); margin-top: var(--s3); }
.legend span { display: inline-flex; align-items: center; gap: 6px; }
.dot { width: 8px; height: 8px; border-radius: 50%; display: inline-block; }
.dot--muted { background: #4d5651; }
.dot--ok { background: var(--ink-soft); }
.dot--best { background: var(--accent); box-shadow: 0 0 0 2px var(--canvas), 0 0 0 3px var(--accent); }
.green__result { padding: var(--s5); }
.green__result table { width: 100%; border-collapse: collapse; font-size: .82rem; margin: var(--s3) 0 var(--s4); }
.green__result th { font-family: var(--f-mono); font-weight: 400; font-size: .68rem; color: var(--ink-mute); text-align: right; padding-bottom: 6px; border-bottom: 1px solid var(--line); }
.green__result th:first-child, .green__result td:first-child { text-align: left; }
.green__result td { text-align: right; padding: 6px 0; font-family: var(--f-mono); font-size: .76rem; border-bottom: 1px solid rgba(169,193,207,.07); }
.green__result td.up { color: var(--bad); }
.green__result td.down { color: var(--ok); }
.saving { font-size: 2rem; font-weight: 760; font-stretch: 115%; letter-spacing: -0.03em; line-height: 1.05; }
.saving small { display: block; font-size: .8rem; font-weight: 400; letter-spacing: 0; color: var(--ink-soft); margin-top: 4px; }

.btn { display: inline-flex; align-items: center; gap: 10px; font: inherit; font-weight: 600; font-stretch: 108%; font-size: .95rem; padding: 14px 22px; border-radius: 999px; border: 0; background: var(--accent); color: var(--accent-ink); cursor: pointer; text-decoration: none; transition: transform .35s var(--ease), box-shadow .35s; box-shadow: 0 10px 30px -12px rgba(255,106,43,.6); }
.btn:hover { transform: translateY(-2px); box-shadow: 0 16px 34px -12px rgba(255,106,43,.7); }
.btn:focus-visible { outline: 2px solid var(--ink); outline-offset: 3px; }
.btn[disabled] { opacity: .6; cursor: progress; }
.btn--ghost { background: transparent; color: var(--ink); border: 1px solid var(--glass-edge); box-shadow: none; }

/* ---------- close ---------- */
.close { width: 100%; max-width: 860px; margin: 0; }
.display--close { font-size: clamp(3.4rem, 8vw, 8rem); margin-bottom: var(--s8); }
.close__cols { display: grid; grid-template-columns: 1fr 1fr; max-width: 860px; gap: var(--s7); margin-bottom: var(--s7); padding: var(--s6); background: var(--glass); border: 1px solid var(--glass-edge); border-radius: 14px; backdrop-filter: blur(18px); -webkit-backdrop-filter: blur(18px); }
.limits { margin: 0; padding-left: 1.1em; color: var(--ink-soft); font-size: .88rem; display: grid; gap: var(--s2); }
.limits li::marker { color: var(--accent); }

/* ---------- reveals ---------- */
.reveal { opacity: 0; transform: translateY(40px); transition: opacity 1.1s var(--ease), transform 1.3s var(--ease); }
.reveal.is-in { opacity: 1; transform: none; }
.display .ln { display: block; overflow: hidden; padding-bottom: .06em; }
.display .ln > span { display: inline-block; transform: translateY(105%); transition: transform 1.3s var(--ease); }
.is-ready .display .ln > span { transform: none; }
.is-ready .display .ln:nth-child(2) > span { transition-delay: .12s; }
.act--hero .lede, .act--hero .eyebrow, .hero__meta { opacity: 0; transform: translateY(16px); transition: opacity 1s .5s, transform 1.2s .5s var(--ease); }
.is-ready .act--hero .lede, .is-ready .act--hero .eyebrow, .is-ready .hero__meta { opacity: 1; transform: none; }

.hudbar { display: none; }

/* ---------- small screens ---------- */
@media (min-width: 1280px) { .rail { display: block; } }
@media (max-width: 1180px) {
  .green { grid-template-columns: 1fr; }
  .green__plot { grid-column: 1; grid-row: auto; }
  .model-charts { width: min(900px, 100%); }
  .lab { grid-template-columns: minmax(300px, 360px) 1fr minmax(210px, 240px); }
}
/* short laptop screens: denser controls so the lab fits without inner scrolling */
@media (max-height: 820px) and (min-width: 901px) {
  .act--lab { padding-top: 84px; padding-bottom: var(--s5); }
  .lab__head { margin-bottom: var(--s3); }
  .lab__head .sub { display: none; }
  .presets { margin-bottom: var(--s3); }
  .chip { padding: 6px 10px; }
  .slider { padding: 4px 0; }
  .slider label { font-size: .82rem; }
  input[type=range] { height: 18px; }
  .lab__row { margin-top: var(--s3); }
  .readout { padding: var(--s4); gap: var(--s4); }
  .act { padding-top: var(--s9); }
}
@media (max-width: 900px) {
  body { font-size: 16px; }
  .rail { display: none; }
  .act { padding: var(--s9) 16px; }
  .copy, .copy--trail, .copy--split { margin: 0; max-width: none; width: 100%; }
  .copy--split { grid-template-columns: 1fr; gap: var(--s4); }
  .act--hero { padding-bottom: 10vh; }
  .display { font-size: clamp(2.6rem, 11.5vw, 3.6rem); }
  .hero__meta { display: none; }
  .act--pour, .act--problem, .act--objectives, .act--data, .act--model { align-items: flex-end; }
  .copy::before { inset: -12% -20%; background: radial-gradient(closest-side, rgba(13,15,14,.9), rgba(13,15,14,.7) 60%, transparent); }
  .facts { grid-template-columns: 1fr; margin: 0; gap: var(--s4); }
  .fact { flex-direction: row; align-items: baseline; gap: var(--s4); }
  .fact__n { font-size: 2.2rem; min-width: 4.6ch; }
  .objectives li { grid-template-columns: 1fr; gap: 4px; }
  .metrics { grid-template-columns: repeat(3, 1fr); gap: var(--s3); }
  .metric b { font-size: 1.5rem; }
  .model-charts { grid-template-columns: 1fr; margin: 0; }
  .spark { width: 70px; }
  .datatable td:nth-child(2), .datatable th:nth-child(2) { display: none; }
  .act--lab { padding-top: 55vh; }
  .lab { grid-template-columns: 1fr; }
  .lab__controls { grid-row: auto; max-height: none; }
  .lab__controls { max-height: none; overflow: visible; }
  .readout { grid-column: 1; grid-row: 1; justify-self: stretch; grid-template-columns: 1fr; gap: var(--s4); padding: var(--s5); }
  .facts { width: 100%; }
  .cards { grid-template-columns: 1fr; }
  .card--wide { grid-column: auto; }
  .green { grid-template-columns: 1fr; }
  .green__plot { grid-column: auto; grid-row: auto; }
  .close__cols { grid-template-columns: 1fr; padding: var(--s5); }
  .hudbar { position: fixed; left: 12px; right: 12px; bottom: 12px; z-index: 30; display: flex; justify-content: space-between; gap: var(--s3); padding: 12px 16px; border-radius: 12px; background: rgba(18,21,20,.82); border: 1px solid var(--glass-edge); backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px); font-family: var(--f-mono); font-size: .78rem; transform: translateY(140%); transition: transform .5s var(--ease); }
  .hudbar.is-on { transform: none; }
  .hudbar b { font-family: var(--f-display); font-size: 1rem; font-stretch: 110%; }
  .hudbar span:nth-child(2) { color: var(--accent); }
}

@media (prefers-reduced-motion: reduce) {
  .reveal, .display .ln > span, .act--hero .lede, .act--hero .eyebrow, .hero__meta { transition: none !important; opacity: 1 !important; transform: none !important; }
  .objectives li { transition: none; }
}