.lecture-number{font-size:13px;font-weight:700}
.path-switch{display:flex;gap:6px;margin:0 0 16px}.path-switch a{flex:1;display:flex;align-items:center;justify-content:center;min-height:44px;padding:10px 7px;text-align:center;border:1px solid #dce3f0;border-radius:6px;font-size:.8rem;font-weight:600;text-decoration:none;background:#fff}.path-switch a[aria-current=page]{background:#224de3;color:#fff;border-color:#224de3}
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@media(min-width:1400px){.lecture-section{max-width:920px}}
@media(max-width:1050px){}
@media(max-width:720px){.lecture-toolbar{top:0}.lecture-overview,.lecture-source,.lecture-passage,.code-lab,.lecture-check,.lecture-finish{padding:18px}.lecture-section{scroll-margin-top:80px;padding:32px 0}.lecture-section>h2{font-size:1.4rem}.code-editor{font-size:13px;padding:14px}.lecture-meta{font-size:.75rem}.lecture-passage blockquote p{font-size:1.05rem}.code-actions{gap:8px 16px}.code-actions .primary{flex:1 1 135px}.lecture-explanation p,.lecture-explanation li{font-size:1rem}.lecture-pager a{flex:1;text-align:center}.lecture-prereqs{font-size:.8rem}.source-notes p{font-size:1rem}}
@media(prefers-reduced-motion:reduce){.lecture-reader *{scroll-behavior:auto}}

.lecture-slide{margin:16px 0}.lecture-slide img{display:block;width:100%;height:auto;border:1px solid #e0e5ee}.lecture-slide figcaption{font-size:.75rem;color:#687a91;margin-top:9px;line-height:1.7}

.passage-player{aspect-ratio:16/9;margin-top:18px;border-radius:8px;overflow:hidden;background:#17263d}.passage-player iframe{width:100%;height:100%;border:0}

.code-lab [hidden]{display:none!important}.code-lab-heading + .code-editor{margin-top:14px}.code-status{font-size:.875rem}