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/* Instrument exhibition: a quiet display case, with a short guided film beside it. */
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.ins-next-row>.primary{flex:1;font-size:14px;border-radius:9px;min-height:46px}
.ins-next-row>.secondary{min-width:46px;border-radius:9px}
.ins-completion-note{font-size:12px;color:var(--muted);display:block;margin-top:8px}
.ins-parts{display:grid;grid-template-columns:1fr 1fr;gap:7px;margin:16px 0}
.ins-parts button{display:flex;align-items:center;gap:7px;text-align:left;padding:8px;font-size:12px;border-radius:8px;min-width:0;min-height:45px;background:#121d21}
.ins-parts b{font:12px Georgia,serif;border:1px solid #5e75604a;border-radius:50%;width:23px;height:23px;flex-shrink:0;display:grid;place-items:center;color:#b4c0ad}
.ins-parts button[aria-pressed=true]{border-color:#d0b77b8c;color:var(--gold);background:#b9a06413}
.ins-part-detail{padding-top:16px;border-top:1px solid var(--line)}
.ins-part-detail .eyebrow{font-size:10px}
.ins-part-detail h4{font-size:16px;line-height:1.7;font-weight:500;margin:8px 0}
.ins-part-detail p{font-size:13px;color:#b9c5bc;line-height:1.85}
.ins-part-detail .ins-detail-note{font-size:12px;color:#94a79f;border-left:1px solid #617d6855;padding-left:10px}
.ins-reassemble{font-size:12px;display:block;margin:6px auto 0;min-height:44px}
.ins-chapters{display:flex;padding:0 22px;background:#080f1380;border-top:1px solid var(--line)}
.ins-chapters button{flex:1;min-width:0;background:none;border:0;border-radius:0;padding:17px 4px;color:#92a39e;font-size:12px;display:flex;align-items:center;justify-content:center;gap:9px;position:relative;min-height:55px}
.ins-chapters button>span{font:11px Georgia,serif;color:#6f8277}
.ins-chapters button[aria-current=step]{color:var(--gold);background:#c3a36909}
.ins-chapters button[aria-current=step]::before{content:'';height:2px;left:14px;right:14px;background:var(--gold);top:-1px;position:absolute}
.ins-chapters button:hover{background:#d1d8ae08}
.ins-footnote{font-size:12px;color:#91a29e;margin-top:17px}
.ins-eye-switch{display:flex;gap:8px;padding:18px 32px 0}
.ins-eye-switch button{font-size:13px;border-radius:8px;background:none;min-width:95px}
.ins-eye-switch button[aria-pressed=true]{color:var(--gold);border-color:var(--gold)}
@media(max-width:900px){
 .ins-story-grid{grid-template-columns:minmax(0,1fr);padding:8px 12px 18px}
 .ins-visual-column{position:static}
 .ins-scene{max-height:440px}
 .ins-story{padding:24px 16px 0}
 .ins-story-top{margin-bottom:13px;padding-bottom:9px}
 .ins-story h3{font-size:22px;margin-bottom:8px}
 .ins-parts{grid-template-columns:repeat(3,minmax(0,1fr))}
 .ins-part-detail{margin-top:20px}
 .ins-player{margin:0 16px}
 .ins-takeaway{margin:17px 0}
 .ins-exhibit-head{padding:22px 26px 0}
}
@media(max-width:540px){
 .instrument-exhibit .page-heading h1{font-size:20px}
 .instrument-exhibit .page-heading p{font-size:12px;max-width:280px;line-height:1.8}
 .ins-tabs{gap:18px;margin-bottom:19px}
 .ins-tabs button{font-size:14px;gap:6px;padding-bottom:13px}
 .ins-tabs button>span{font-size:10px}
 .ins-exhibit{border-radius:16px}
 .ins-exhibit-head{padding:21px 20px 0;gap:8px}
 .ins-exhibit-head .eyebrow{font-size:10px}
 .ins-exhibit-head h2{font-size:19px;line-height:1.65;max-width:240px;margin-top:5px;text-wrap:balance}
 .ins-edition{font-size:34px;align-self:flex-start;margin-top:10px}
 .ins-edition small{display:none}
 .ins-story-grid{padding:0 4px 12px}
 .ins-scene{aspect-ratio:960/650}
 .ins-label{font-size:32px}
 .ins-label.part-number{font-size:23px}
 .camera-position-0{transform:translate(190px,180px)}
 .camera-position-1{transform:translate(485px,180px)}
 .camera-position-2{transform:translate(775px,180px)}
 .camera-position-3{transform:translate(190px,447px)}
 .camera-position-4{transform:translate(485px,427px)}
 .camera-position-5{transform:translate(775px,427px)}
 .ins-scene:has(.camera-position) .assembly-guide{display:none}
 .ins-player{margin:0 12px;gap:6px;flex-wrap:wrap}
 .ins-player button{font-size:12px;padding:8px 12px;min-width:76px}
 .ins-player #ins-play-status{font-size:10px;max-width:112px}
 .ins-progress{margin:12px 12px 0}
 .ins-legend{margin:12px 12px 0;font-size:10px;gap:5px}
 .ins-story{padding:21px 14px 0}
 .ins-story h3{font-size:20px;line-height:1.6}
 .ins-copy,.ins-takeaway p{font-size:14px;line-height:1.9}
 .ins-parts{grid-template-columns:1fr 1fr}
 .ins-parts button{font-size:12px;min-height:47px}
 .ins-chapters{padding:0 6px}
 .ins-chapters button{font-size:11px;flex-direction:column;gap:5px;padding:12px 2px;line-height:1.5}
 .ins-chapters button[aria-current=step]::before{left:4px;right:4px}
 .ins-footnote{font-size:11px}
 .ins-eye-switch{padding:16px 20px 0}
}
@media(max-width:900px){.instrument-grid,.advanced-grid{grid-template-columns:minmax(0,1fr)}}
/* Playback remains in view while students watch the optical bench. */
.stage-shell{position:relative}
.stage-playback{position:absolute;left:16px;bottom:46px;display:flex;gap:8px;z-index:2}
.stage-playback button{min-height:40px;padding:8px 14px;font-size:.875rem;box-shadow:0 4px 16px #0005}
.stage-playback button[hidden]{display:none}
.stage-shell:has(#stage) .stage-playback{right:16px;align-items:center}
.stage-expand,.stage-restore{margin-left:auto}
.stage-playback .stage-expand{width:44px;height:44px;min-height:44px;padding:0;flex-shrink:0}
.stage-expand span{font-size:1.6em;line-height:1}
.workspace>.lab-toolbar{margin:16px 0 12px}
/* Native modal focus containment; portrait phones rotate the viewing canvas only. */
html.lab-wide-open,html.lab-wide-open body{overflow:hidden;overscroll-behavior:none}
dialog.lab-wide-view{position:fixed;inset:0;margin:0;padding:0;width:100vw;width:100dvw;height:100vh;height:100dvh;max-width:none;max-height:none;border:0;border-radius:0;background:#0c1216;overflow:hidden}
.lab-wide-view::backdrop{background:#090d10;backdrop-filter:none}
.lab-wide-view .stage-shell{width:100%;height:100%;padding:8px 12px max(8px,env(safe-area-inset-bottom));display:flex;flex-direction:column;border:0;border-radius:0;box-shadow:none;background:#0c1216}
.lab-wide-view .stage{flex:1;min-height:0;aspect-ratio:auto;border-radius:0}
.lab-wide-view .stage-shell .stage-playback{position:static;flex-shrink:0;padding:5px max(4px,env(safe-area-inset-right)) 0 max(4px,env(safe-area-inset-left));gap:12px}
.lab-wide-view .stage-playback button{min-height:44px;font-size:.9rem;padding:8px 16px}
.lab-wide-view .stage-note,.lab-wide-view .stage-expand,.lab-wide-view #pause-button{display:none!important}
.lab-wide-view .graph-label{font-size:24px}
.lab-wide-view .graph-small{font-size:20px}
@media(orientation:portrait){
 dialog.lab-wide-view{inset:auto;left:50%;top:50%;width:100vh;width:100dvh;height:100vw;height:100dvw;transform:translate(-50%,-50%) rotate(90deg)}
 .lab-wide-view .stage-shell{padding:8px max(12px,env(safe-area-inset-bottom)) 8px max(12px,env(safe-area-inset-top))}
}
@media(max-width:540px){.stage-playback{left:12px;bottom:43px}.stage-playback button{padding:7px 11px}}

/* The optional mirror area shares the lab, palette and accessible controls. */
.lab-area-tabs{display:flex;gap:8px;margin:0 0 24px;border-bottom:1px solid var(--line);padding-bottom:12px}
.lab-area-tabs a{display:flex;gap:9px;align-items:center;padding:10px 16px;border:1px solid transparent;border-radius:12px;color:var(--muted);text-decoration:none}
.lab-area-tabs a.active{color:var(--gold);background:#d6bc7d0d;border-color:#c6ad7044}
.lab-area-tabs small{font-size:.7rem;color:var(--muted);letter-spacing:.04em}
.mirror-picker{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:8px;margin:0 0 14px}
.mirror-picker button.active{border-color:var(--gold);color:var(--gold);background:#c7ad7310}
.mirror-stage{aspect-ratio:1.95}
.mirror-stage [data-mirror-drag]{cursor:ew-resize;touch-action:none}
.mirror-stage [data-mirror-drag]:focus-visible{outline:2px solid var(--mint);outline-offset:3px}
.mirror-observations{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin:18px 0}
.mirror-observations>div{padding:12px;border:1px solid var(--line);border-radius:12px;background:#ffffff03}
.mirror-observations strong{display:block;font-size:.85rem;line-height:1.65;margin-top:7px;font-weight:500;color:var(--mint)}
.mirror-life{margin-top:20px}
.mirror-life h3{margin-top:10px}.mirror-life p{font-size:.9rem;color:var(--muted);line-height:1.8;margin-bottom:0}
.mirror-board{grid-template-columns:repeat(3,minmax(0,1fr))}
.mirror-board .board-tile{text-align:left;min-height:160px}
.mirror-panel .feedback{margin-bottom:16px}
.mirror-grid .mirror-checks{margin:16px 0}
.mirror-grid #mirror-result{margin-top:18px}
@media(max-width:900px){.mirror-grid.observing .mirror-panel .mirror-extra{display:none}.mirror-grid.observing .mirror-instruction{margin-bottom:0;font-size:.8rem}.mirror-grid.observing .mirror-panel [data-mirror-action=hint]{display:none}.mirror-grid.observing .mirror-panel .mission-head{font-size:.72rem}.mirror-grid .mission-panel{position:static}.mirror-stage{min-height:270px;aspect-ratio:1.45}}
@media(max-width:540px){.lab-area-tabs{margin-bottom:18px;padding-bottom:9px}.lab-area-tabs a{padding:8px 11px;font-size:.9rem}.mirror-picker{gap:5px}.mirror-picker button{padding:8px 5px;font-size:.9rem}.mirror-board{grid-template-columns:1fr}.mirror-board .board-tile{min-height:100px}.mirror-observations{gap:6px}.mirror-observations>div{padding:9px}.mirror-observations strong{font-size:.78rem}.mirror-diagram .graph-label{font-size:28px}.mirror-diagram .graph-small{font-size:27px}.mirror-stage{min-height:252px}.mirror-stage~.stage-playback{bottom:43px}}
.mirror-grid input[type=range]{min-height:44px}
@media(max-width:900px){.mirror-free .mirror-panel .eyebrow,.mirror-free .mirror-panel p,.mirror-free .mirror-panel button{display:none}.mirror-free .mirror-panel h2{margin:0;font-size:1.2rem}.mirror-free .mirror-panel .panel{padding:14px 16px}}
/* A minimum height must not let aspect-ratio widen the bench past its parent. */
.stage{width:100%}
/* Quiz figures keep the supplied orientation and proportions on a white sheet. */
.quiz-tracks{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;margin:22px 0}
.quiz-tracks button{text-align:left;display:flex;flex-direction:column;gap:10px;min-width:0;padding:22px}
.quiz-tracks strong{font-size:1.25rem}.quiz-tracks button>span:not(.eyebrow),.quiz-tracks small{color:var(--muted);font-size:.85rem;line-height:1.6}
.quiz-tracks .active{border-color:var(--gold);background:#c7ad7310}.quiz-tracks button:disabled{opacity:.75}
.quiz-panel{scroll-margin-top:100px}.quiz-question{font-weight:500;line-height:1.9;overflow-wrap:anywhere}
.quiz-figures{display:flex;flex-wrap:wrap;justify-content:center;gap:14px;margin:20px 0}
.quiz-figures figure{margin:0;max-width:100%;min-width:0;flex:1 1 260px;text-align:center}
.quiz-figures figure:only-child{flex:0 1 680px}.quiz-figure-button{width:100%;padding:12px;background:#fff;cursor:zoom-in;border:1px solid var(--line)}
.quiz-figure{display:block;width:100%;height:auto;max-height:360px;object-fit:contain;background:white;border-radius:5px}
.quiz-figures figcaption{margin-top:7px;font-size:.85rem;color:var(--mint)}
.quiz-figures.many{display:grid;grid-template-columns:repeat(3,minmax(0,1fr))}.quiz-figures.many .quiz-figure{height:180px}
.quiz-image-hint{text-align:center;margin-top:-8px}
.quiz-choices.with-figures{grid-template-columns:repeat(2,minmax(0,1fr))}
.quiz-choices .choice{min-width:0;min-height:48px;line-height:1.7}.quiz-option-content{flex:1;min-width:0;white-space:pre-wrap;overflow-wrap:anywhere}
.quiz-option-content .quiz-figures{margin:10px 0 0}.quiz-option-content .quiz-figures figure{flex:1}
.quiz-option-content .quiz-figure{height:220px;padding:8px}.quiz-choices .incorrect{border-color:#ce8f83}
.quiz-feedback p{white-space:pre-wrap;overflow-wrap:anywhere;line-height:1.9}.quiz-zoom{display:block;width:100%;height:auto;background:white;border-radius:8px}
.quiz-zoom-scroll{overflow:auto;background:white;border-radius:8px}.quiz-zoom-scroll .quiz-zoom{width:max(100%,700px);max-width:none}.quiz-zoom-scroll:focus-visible{outline:2px solid var(--mint);outline-offset:4px}dialog:has(.quiz-zoom-scroll){width:min(1000px,calc(100% - 24px))}
.review-row p{white-space:pre-wrap;overflow-wrap:anywhere}
@media(max-width:540px){.quiz-tracks{grid-template-columns:1fr;gap:10px}.quiz-tracks button{padding:16px;gap:6px}.quiz-tracks strong{font-size:1.1rem}.quiz-choices.with-figures{grid-template-columns:1fr}.quiz-option-content .quiz-figure{height:210px}.quiz-figures.many{grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}.quiz-figures.many .quiz-figure{height:120px}.quiz-figure-button{padding:8px}}
.quiz-tracks.in-round{grid-template-columns:repeat(2,minmax(0,1fr));margin:14px 0}.quiz-tracks.in-round button{padding:12px;min-height:48px}.quiz-tracks.in-round strong{font-size:1rem}.quiz-tracks.in-round span,.quiz-tracks.in-round small{display:none}
@media(max-width:540px){.mirror-diagram .graph-label{font-size:38px}.mirror-diagram .graph-small{font-size:33px}}

@media(prefers-reduced-motion:reduce){.ray-arrow-wait{animation:none;opacity:1}}