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/* Keep the visible track thin, with a comfortable touch target. */
input[type=range]{height:24px;background:transparent;margin-top:-8px;margin-bottom:-8px}input[type=range]::-webkit-slider-runnable-track{height:4px;border-radius:5px;background:linear-gradient(to right,#9ea58a 0%,#9ea58a var(--fill),#e3e6dc var(--fill),#e3e6dc 100%)}input[type=range]::-moz-range-track{height:4px;border-radius:5px;background:linear-gradient(to right,#9ea58a 0%,#9ea58a var(--fill),#e3e6dc var(--fill),#e3e6dc 100%)}input[type=range]::-webkit-slider-thumb{margin-top:-4.5px}@media(max-width:620px){input[type=range]{height:30px;margin-top:-11px;margin-bottom:-11px}input[type=range]::-webkit-slider-thumb{margin-top:-6.5px}}

@media(max-width:620px){.lab{overflow:visible}.scene-column{position:sticky;top:0;z-index:3;border-radius:12px 12px 0 0;overflow:hidden;box-shadow:0 6px 12px #222b0d10}.viewport{height:85vw;min-height:285px;max-height:340px}.controls{border-radius:0 0 12px 12px;background:var(--panel)}.source-tag #source-label{display:none}.source-orb{width:27px;height:27px;font-size:20px}}

@media(max-width:620px){h1{font-size:clamp(32px,9vw,38px)}.controls input,.controls button,.controls svg[tabindex]{scroll-margin-top:calc(var(--sticky-scene-height,430px) + 35px);scroll-margin-bottom:30px}.scene-observation{min-height:74px}.scene-observation p{font-size:9px}}

/* Course attribution and a quiet invitation after the practical exercises. */
.course-name{display:flex;align-items:center;gap:17px}.course-name a{color:#636d55;text-decoration:none;padding:8px 0;transition:color .2s}.course-name a:hover{color:var(--accent)}.course-name .external-arrow{margin:0 0 0 4px;color:inherit}.course-name .course-author{margin:0;padding-left:17px;border-left:1px solid var(--line);color:#8b907f;font-size:11px}
.lab-invitation{display:grid;grid-template-columns:minmax(0,1.55fr) minmax(250px,1fr);background:#30372c;color:#f1f0e6;border:1px solid #3e4738;border-radius:15px;margin:0 0 32px;padding:36px 40px;gap:42px;overflow:hidden}.invitation-eyebrow{display:flex;align-items:center;gap:9px;color:#bbc4aa;font-size:9px;font-weight:500;letter-spacing:1.25px;line-height:1.6}.invitation-symbol{display:inline-block;width:17px;height:17px;flex-shrink:0;border-radius:50%;background:linear-gradient(120deg,#edb083 50%,#edb08324 50%)}.invitation-copy h2{font-size:36px;font-weight:500;letter-spacing:-1.1px;line-height:1.15;margin:20px 0 16px}.invitation-copy h2 em,.selected-motto em{font-family:Georgia,"Times New Roman",serif;font-weight:400;color:#e5a77d}.invitation-copy p{color:#c2cab8;font-size:13px;line-height:1.8;max-width:510px}.invitation-cta{display:inline-flex;align-items:center;gap:25px;background:#e9a375;color:#2d3026;text-decoration:none;font-size:12px;font-weight:550;padding:14px 19px;border-radius:7px;margin-top:24px;transition:background .2s,transform .2s}.invitation-cta:hover{background:#f3b68d;transform:translateY(-1px)}.invitation-cta span{font-size:18px;line-height:1}.invitation-domain{font-size:10px;color:#a4b095;margin-left:15px}.invitation-selected{border-left:1px solid #59614c;padding-left:40px;display:flex;flex-direction:column;justify-content:center}.selected-caption{color:#bac4ac;font-size:9px;letter-spacing:1.25px;line-height:1.7}.selected-motto{font-size:30px;font-weight:400;line-height:1.18;letter-spacing:-.7px;margin:20px 0 14px}.invitation-selected p{font-size:12px;line-height:1.8;color:#bcc6b0;max-width:280px}.selected-link{color:#f0eadb;font-size:12px;display:inline-flex;gap:24px;justify-content:space-between;align-self:flex-start;text-decoration:none;border-bottom:1px solid #7e896e;padding:10px 0 8px;margin-top:12px;transition:color .2s,border-color .2s}.selected-link:hover{color:#efb38a;border-color:#efb38a}.selected-link span{font-size:18px;line-height:1}.selected-domain{font-size:9px;color:#a4b095;margin-top:9px}footer a{color:#727e62;text-decoration:none;border-bottom:1px solid #cbd1bf;padding-bottom:2px}footer a:hover{color:var(--accent);border-color:var(--accent)}
@media(max-width:900px){.lab-invitation{padding:30px;gap:28px;grid-template-columns:minmax(0,1.4fr) minmax(210px,1fr)}.invitation-selected{padding-left:27px}.invitation-copy h2{font-size:30px}.invitation-copy p{font-size:12px}.invitation-domain{display:block;margin:10px 0 0}.course-name{gap:10px}.course-name .course-author{font-size:10px;padding-left:10px}.selected-motto{font-size:27px}}
@media(max-width:620px){.site-header{height:auto;min-height:78px;flex-wrap:wrap;gap:3px 12px;padding-top:13px;padding-bottom:10px}.site-header>.brand{order:0}.site-header>#help-button{order:1}.course-name{display:flex;order:2;flex-basis:100%;max-width:none;margin:0;text-align:left;font-size:10px}.course-name a{padding:5px 0}.course-name .external-arrow{display:inline}.course-name .course-author{display:none}.lab-invitation{grid-template-columns:1fr;gap:25px;padding:25px 22px;margin-bottom:24px;border-radius:12px}.invitation-eyebrow{font-size:8px;letter-spacing:.8px;gap:8px}.invitation-symbol{width:15px;height:15px}.invitation-copy h2{font-size:30px;margin-top:18px}.invitation-copy p{font-size:12px;line-height:1.85}.invitation-cta{font-size:12px;padding:14px 16px;margin-top:20px;min-height:46px;display:flex;justify-content:space-between}.invitation-domain{margin-top:9px;font-size:9px}.invitation-selected{border-left:0;border-top:1px solid #59614c;padding:24px 0 0}.selected-caption{font-size:8px;letter-spacing:1px}.selected-motto{font-size:27px;margin:14px 0 10px}.selected-motto br{display:none}.invitation-selected p{max-width:none;font-size:12px}.selected-link{min-height:44px;margin-top:8px}.selected-domain{font-size:9px}footer{line-height:1.8}}

.light-theory{margin-top:18px;border:1px solid var(--line);border-radius:12px;background:#f9faf4;overflow:hidden}.light-theory summary{list-style:none;display:flex;align-items:center;gap:13px;padding:18px 23px;cursor:pointer}.light-theory summary::-webkit-details-marker{display:none}.light-theory summary:focus-visible{outline:2px solid var(--accent);outline-offset:-4px}.theory-mark{width:29px;height:29px;display:grid;place-items:center;border:1px solid #b9c2ab;border-radius:50%;color:#788669;font-size:15px;flex-shrink:0}.light-theory summary strong{font-size:14px;font-weight:550}.light-theory summary small{display:block;font-size:11px;color:#7e8972;margin-top:5px}.theory-toggle{font-size:23px;font-weight:300;margin-left:auto;color:#869576}.light-theory[open] .theory-toggle{transform:rotate(45deg)}.theory-content{padding:0 23px 23px}.theory-intro{font-size:12px;line-height:1.7;color:#77816b;border-top:1px solid var(--line);padding:18px 0}.term-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}.term{position:relative;padding:21px 18px 17px;border:1px solid #e0e4d7;border-radius:9px;background:#fdfdf9;display:flex;flex-direction:column}.term-number{font-size:9px;letter-spacing:1px;color:#97a288;margin-bottom:12px}.term h3,.theory-distinction h3{font-weight:550;font-size:15px;letter-spacing:-.2px;margin:0 0 10px}.term p,.theory-distinction p{font-size:12px;line-height:1.8;color:#68735d;margin:0 0 13px}.term button,.theory-distinction button{background:none;color:#667d4d;font-size:11px;text-align:left;align-self:flex-start;line-height:1.6;padding:9px 0 3px;border-bottom:1px solid #bdc9ac;margin-top:auto;min-height:36px}.term button span,.theory-distinction button span{margin-left:8px;color:var(--accent)}.term button:hover,.theory-distinction button:hover{color:var(--accent);border-color:var(--accent)}.term-note{font-size:10px;line-height:1.8;color:#859077;padding-top:10px;border-top:1px solid #e5e8dd;margin-top:auto}.theory-distinction{display:grid;grid-template-columns:1fr 1fr;gap:28px;margin-top:18px;padding:23px;background:#edf0e5;border-radius:9px}.theory-distinction .control-caption{display:block;font-size:8px;letter-spacing:1px;margin-bottom:10px}.theory-distinction h3{font-size:16px;line-height:1.4}.theory-distinction .contrast-example{font-size:10px;color:#81916f;margin-bottom:0}.theory-distinction button{margin-top:0}.theory-distinction article{display:flex;flex-direction:column}@media(max-width:900px){.term-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}@media(max-width:620px){.light-theory{margin-top:15px}.light-theory summary{padding:16px;gap:10px}.light-theory summary strong{font-size:13px}.light-theory summary small{font-size:10px}.theory-content{padding:0 15px 15px}.theory-intro{font-size:11px}.term-grid{grid-template-columns:1fr;gap:9px}.term{padding:16px}.term-number{margin-bottom:8px}.term h3{font-size:14px}.term p{font-size:12px}.term button,.theory-distinction button{min-height:44px}.theory-distinction{grid-template-columns:1fr;gap:21px;padding:17px;margin-top:12px}.theory-distinction article+article{border-top:1px solid #d2dbc5;padding-top:20px}.theory-distinction h3{font-size:15px}}

.glass-note{font-size:11px;line-height:1.8;color:#7b856e;padding:13px 17px;margin-top:12px;border-left:2px solid #c0cbaF;background:#edf0e5;border-radius:0 7px 7px 0}@media(max-width:620px){.object-switch button{padding:7px 10px}.camera-label{font-size:7px;letter-spacing:.3px}.glass-note{font-size:10px;padding:11px 13px}}

.object-switch,.compare-controls button{backdrop-filter:none}

/* A light/shadow disk replaces the star, matching the trainer's own identity. */
.light-disc{display:inline-block;border-radius:50%;background:linear-gradient(120deg,#83916d 50%,#dce2d0 50%);border:1px solid #a5b294;flex-shrink:0}.tiny-star.light-disc{width:15px;height:15px}.practice-icon.light-disc{width:30px;height:30px;margin-top:0}.practice{align-items:center}.practice-body{min-width:0;flex:1}.practice-heading{display:flex;align-items:center;gap:15px;margin-bottom:9px}.practice-heading .control-caption{color:#7d876e}#challenge-count{color:#929d83;font-size:10px;font-variant-numeric:tabular-nums;white-space:nowrap}#challenge-select{display:block;width:100%;max-width:530px;font:inherit;font-size:13px;color:#4d5941;border:1px solid #cdd5c0;border-radius:6px;background:#f9faf4;padding:9px 30px 9px 10px;min-height:40px;cursor:pointer;text-overflow:ellipsis}#challenge-select:focus-visible{outline:2px solid var(--accent);outline-offset:3px}.practice p{margin-top:10px;max-width:770px;line-height:1.8}.practice button{min-height:44px;flex-shrink:0}@media(max-width:620px){.practice{gap:12px;align-items:flex-start}.practice-icon.light-disc{width:25px;height:25px;margin-top:3px}.practice-body{flex-basis:calc(100% - 38px)!important}.practice-heading{gap:8px;justify-content:space-between}.practice-heading .control-caption{font-size:7px;letter-spacing:.7px}#challenge-select{font-size:11px;padding-left:8px;min-height:44px}#challenge-count{font-size:9px}.practice button{margin-left:37px}.practice p{font-size:11px}}

.reflector-panel{margin-top:15px}.reflector-panel .exposure-row{padding-top:15px}.reflector-explanation{font-size:10px;line-height:1.8;color:#78866c;margin:12px 0 15px}.reflector-hint{font-size:9px;line-height:1.7;color:#8a967e}.reflector-panel .control{margin-bottom:12px}.reflector-panel .exposure-row p{max-width:200px}@media(max-width:620px){.reflector-explanation{font-size:11px}.reflector-hint{font-size:10px}.reflector-panel .control{margin:18px 0}.reflector-panel .exposure-row label{font-size:12px}}

@media(min-width:621px){.scene-column,.controls{height:740px}.viewport{min-height:0}.controls{overflow-y:auto;scrollbar-width:thin;scrollbar-color:#cdd5c0 transparent}.scene-observation{min-height:104px;flex-shrink:0}}

/* Give the light orbit its own full-width touch surface. */
.orbit-section{flex-direction:column;align-items:center;gap:8px}.orbit-copy{width:100%;gap:5px}.orbit-help br{display:none}.orbit-help br::after{content:" "}#orbit{width:min(100%,240px);height:auto;aspect-ratio:160/148;flex-shrink:0}

/* Laboratory brand and aligned column headings. */
.lab-invitation{background:#111111;border-color:#292929;color:#f5f5f2}
.invitation-selected{justify-content:flex-start;border-color:#363636}
.invitation-eyebrow,.selected-caption{display:flex;align-items:center;min-height:17px;font-size:9px;line-height:17px;letter-spacing:1.25px;color:#b9b9b5}
.invitation-symbol{background:linear-gradient(120deg,#ff6400 50%,#ff640033 50%)}
.invitation-copy h2,.selected-motto{font-size:36px;font-weight:500;line-height:1.15;letter-spacing:-1.1px;margin:20px 0 16px}
.invitation-copy h2 em,.selected-motto em{color:#ff6400}
.invitation-copy p,.invitation-selected p{color:#c5c5c1;line-height:1.8}
.invitation-copy p+p{margin-top:16px}
.invitation-copy .invitation-start{color:#ff6400;font-weight:550}
.lab-invitation .invitation-cta{align-self:flex-start;background:#ff6400;color:#111111;border:0;min-height:46px;align-items:center}
.lab-invitation .invitation-cta:hover{background:#ff7c28}
.invitation-domain,.selected-domain{color:#999994}
@media(max-width:900px){.invitation-copy h2,.selected-motto{font-size:30px}}
@media(max-width:620px){.invitation-eyebrow,.selected-caption{font-size:8px;letter-spacing:.8px}.invitation-copy h2,.selected-motto{margin:18px 0 16px}.lab-invitation .invitation-cta{display:flex;align-self:stretch}.selected-domain{margin-top:9px}}

.portrait-status{position:absolute;left:50%;top:50%;transform:translate(-50%,-50%);max-width:80%;padding:12px 18px;border-radius:12px;background:#171b16ed;color:#fff;font-size:13px;text-align:center;pointer-events:none}.portrait-status[hidden]{display:none}