@import url('https://fonts.googleapis.com/css2?family=DM+Sans:wght@400;450;500;550;600;650;700&family=Noto+Sans+Arabic:wght@400;500;600;700&display=swap');
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@media(min-width:1700px){#viewport{height:580px}.control-panel{padding:25px}.workspace{grid-template-columns:minmax(0,1fr) 320px}.parameter label,.part-button{font-size:14px}}@media(max-width:1250px){.app-layout{grid-template-columns:200px minmax(0,1fr)}main{padding:28px 20px}.library{padding-inline:12px}.lesson{padding-inline:7px;gap:7px}.lesson-symbol{flex-basis:26px;height:29px;font-size:23px}.lesson-arrow{display:none}.workspace{grid-template-columns:minmax(0,1fr) 260px;gap:14px}.control-panel{padding:19px 15px}.top-caption{display:none}.viewer-hint{font-size:10px;padding:12px}.viewer-hint>div{gap:8px}.playback{gap:7px;padding-inline:12px}.playback-label{max-width:100px}.speed-label>span{display:none}.learn-panel{grid-template-columns:1fr 1.5fr}.challenge{grid-column:1/-1;border-inline-start:0;border-top:1px solid var(--line);padding:14px 0 0}.challenge strong{display:inline;margin-inline-end:12px}.lesson strong{font-size:13px}}@media(max-width:1050px){.app-layout{display:block}.library{padding:15px 22px;border-inline-end:0;border-bottom:1px solid var(--line)}.library>.eyebrow,.library>h2,.library-bottom{display:none}.lesson-list{display:flex;gap:10px}.lesson{flex:1;align-items:center;padding:10px 13px}.lesson small,.lesson em{display:none}.lesson strong{margin:0;font-size:14px}.lesson.active:before{display:none}.lesson-symbol{flex-basis:30px;height:31px}.lesson-header h1{font-size:30px}.workspace{grid-template-columns:minmax(0,1fr) 280px}main{padding:24px}.lesson-header{margin-bottom:20px}.viewer-hint>span{max-width:160px;line-height:1.7}.scene-badge{font-size:11px}#viewport{height:455px}}@media(max-width:760px){.topbar{height:72px;padding-inline:18px}.brand{font-size:22px}.brand-icon{width:36px;height:38px;font-size:34px;line-height:37px}.level-tag{display:none}.header-actions{gap:5px}.library{padding:12px}.lesson{padding:10px 6px;justify-content:center;gap:7px}.lesson strong{font-size:12px}.lesson-symbol{flex-basis:25px;height:26px;font-size:20px}.workspace{grid-template-columns:1fr}.lesson-header{align-items:flex-start}.scene-badge{display:none}.lesson-header h1{font-size:27px}.lesson-header p{font-size:13px}.lesson-header .eyebrow{font-size:10px}main{padding:23px 14px}.control-panel{padding:22px}.control-panel #parameters{display:grid;grid-template-columns:1fr 1fr;gap:20px}.parameter{margin-bottom:12px}.parts-list{grid-template-columns:1fr 1fr}.readouts{margin:12px 0 22px}.readout strong{font-size:24px}.learn-panel{grid-template-columns:1fr;padding:22px;gap:17px}.learn-heading h2{font-size:19px}#explanation,.challenge{font-size:14px}.learn-heading .eyebrow{font-size:11px}.challenge{grid-column:auto}#viewport{height:430px}.viewer-hint>span{max-width:none;font-size:10px}.viewer-hint #autoRotate{font-size:10px}.playback-label{max-width:140px}.timeline{margin-inline:9px}.parameter label,.part-button{font-size:14px}.model-note{font-size:12px}.range-limits{font-size:11px}.readout span{font-size:12px}.playback-label strong{font-size:13px}.panel-heading .eyebrow{font-size:12px}}@media(max-width:390px){.lesson-symbol{display:none}.lesson strong{font-size:11px}.viewer-hint>div{gap:6px}.viewer-hint>span{max-width:145px}.control-panel #parameters{grid-template-columns:1fr}.language-btn{font-size:13px}#viewport{height:370px}}@media(prefers-reduced-motion:reduce){.loader{animation:none}}@media(min-width:761px){.parameter label,.parts-heading h3{font-size:14px}.part-button{font-size:14px}.model-note{font-size:12px}.lesson em{font-size:12px}.lesson small{font-size:12px}.lesson strong{font-size:14px}.readout span{font-size:12px}.viewer-hint{font-size:12px}.view-modes button{font-size:14px}.playback-label strong{font-size:14px}.playback-label span{font-size:12px}.text-button{font-size:12px}.learn-heading .eyebrow{font-size:12px}#explanation,.challenge{font-size:14px}.range-limits{font-size:12px}.eyebrow{font-size:12px}}