@font-face{font-family:Inter;src:url('../shared/fonts/InterVariable.woff2') format('woff2');font-weight:100 900;font-display:swap}
:root{font-family:Inter,system-ui,sans-serif;color:#0b2a5b;background:#f6f8fb;font-synthesis:none;line-height:1.6;font-size:16px;--muted:#334155;--line:#d6e2f5;--accent:#1d4ed8}
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@media(max-width:800px){.subject{padding:15px 12px;gap:9px}.subject[aria-pressed=true]{padding:14px 11px}.subject-icon{width:32px;height:38px;font-size:20px}.subject-text>span{font-size:10px}.subject-arrow{display:none}}
@media(max-width:600px){.generator{padding:0 20px}.site-header{padding:20px 0}.header-note{display:none}.intro{padding:35px 0 29px}h1{font-size:2.5rem}.lede{font-size:14px}.subject-grid{grid-template-columns:1fr;gap:8px}.subject{padding:12px 15px;gap:13px}.subject[aria-pressed=true]{padding:11px 14px}.subject-icon{height:37px;width:38px}.subject-text>span{font-size:11px}.subject-arrow{display:block;align-self:center}.section-heading>span{font-size:10px}.subject-text strong{font-size:15px}.section-heading h2{font-size:14px}#question-view{padding:20px 18px}.question-heading h2{font-size:21px}.question-heading>span{font-size:9px}.context{padding:13px;font-size:14px}.actions{gap:8px}.actions button{flex:1;padding:10px;white-space:nowrap}.actions .next{flex-basis:100%;margin-left:0}.tip{display:block}.tip p{margin-top:5px}.intro-meta{gap:12px;font-size:11px}.intro-meta span+span::before{margin-right:10px}.steps{gap:18px;font-size:10px}.welcome h2{font-size:20px}}
@media(prefers-reduced-motion:reduce){*{transition:none!important}}

/* ZornScience activity branding and toolbar. */
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.generator .zsa-th-brand {display:inline-flex;align-items:center;flex-shrink:0;min-height:52px;min-width:52px;text-decoration:none;color:var(--zsa-navy);}
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.zsa-th-icon {width:18px;height:18px;flex-shrink:0;}
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.generator h1 {min-width:0;font-size:clamp(1.6rem,1.2rem + 1.2vw,2rem);letter-spacing:-.035em;line-height:1.15;margin:0;font-weight:650;}
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.zsa-th-share-panel {margin-top:14px;padding:20px;border:1px solid #cdd9e9;border-radius:12px;background:white;box-shadow:0 7px 20px rgba(11,42,91,.06);}
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.zsa-th-instructions-equation {margin:6px 0 13px!important;color:var(--zsa-navy);font-size:22px;line-height:1.5;}
.zsa-th-instructions-equation:last-child {margin-bottom:0!important;}
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.zsa-th-instructions-note {margin-top:16px!important;font-size:13px;color:#536075;}
body{background:#edf2f7}.zsa.generator{--zsa-max-width:1120px;max-width:1120px;padding:28px 36px;background:#f6f8fb;font:400 16px/1.6 Inter,system-ui,sans-serif;color:var(--zsa-slate)}
.generator .zsa-th-header{margin-bottom:0}.generator .zsa-th-brand{padding:8px;background:white;border:1px solid #dce5ef;border-radius:15px}.generator .zsa-th-brand img{width:52px;height:auto}.generator h1{font-size:clamp(1.4rem,1rem + 1vw,1.85rem);margin:0;font-weight:650;letter-spacing:-.035em}.generator .activity-subtitle{font-size:13px;margin:5px 0 0;color:#536782}.generator .zsa-btn{font-size:13px;padding:10px 14px;border-color:#c7d6ee}.generator .zsa-btn--primary{border-color:#1d4ed8}.generator .intro{padding:24px 0 28px}.generator .lede{margin-bottom:14px}.generator .section-heading h2{font-size:15px;font-weight:650;margin:0}.generator .welcome h2{font-size:22px;margin:8px 0;font-weight:600}.generator .question-heading h2{font-size:24px;font-weight:600;letter-spacing:-.6px;line-height:1.25;margin:20px 0 5px}.generator .answer h3{font-size:15px;font-weight:650;margin:0 0 8px}.generator .zsa-th-share-heading h2{font-size:18px;font-weight:600;margin:0}.generator .zsa-th-instructions-heading h2{font-size:23px;font-weight:600;margin:0}.generator .zsa-th-share-link{flex-wrap:wrap}.generator .zsa-th-instructions ol{padding-left:23px}.generator .zsa-th-instructions li{margin:12px 0}.generator .zsa-th-share-panel p{margin:8px 0}.generator.zsa--embedded{padding-top:12px}
@media(max-width:650px){.zsa.generator{padding:18px 16px}.generator .zsa-th-identity{flex-basis:100%}.generator .zsa-th-header-tools{margin-left:0}.generator .zsa-th-topline{gap:14px}.generator .zsa-th-brand img{width:42px}.generator h1{font-size:22px}.generator .question-heading h2{font-size:21px}.generator .section-heading h2{font-size:14px}.generator .welcome h2{font-size:20px}.generator .zsa-th-share-panel{padding:16px}.generator .zsa-th-instructions{padding:20px}.generator .intro{padding:20px 0 24px}}

/* Compact activity header; subject selection is the first content row. */
.generator .subjects{margin-top:24px}
@media(max-width:650px){.generator .subjects{margin-top:20px}.generator .zsa-th-identity{flex:1 1 100%}.generator .zsa-th-identity>div{min-width:0}.generator h1{overflow-wrap:break-word}.generator .zsa-th-header-buttons{flex-wrap:wrap}.generator .zsa-th-share-link input{flex-basis:100%}}