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a{display:block;font-size:11px;line-height:1.7;color:#94a78b;text-decoration:none;padding:4px 0;overflow-wrap:anywhere}.lesson-toc a:hover{color:#e3c46f}.lesson-toc .lesson-toc-back{margin-top:18px;border-top:1px solid #3b4635;padding-top:16px;color:#c8ba7a}.lesson-article{min-width:0;max-width:900px}.lesson-reading-note{background:#243025;border:1px solid #45553c;border-left:3px solid #a5ba78;border-radius:8px;padding:18px 21px;margin-bottom:32px}.lesson-reading-note strong{font-size:13px;color:#d9e4ca}.lesson-reading-note p{font-size:12px;line-height:1.9;margin:8px 0 0;color:#a5b69a}.lesson-content-section{scroll-margin-top:100px;padding:0 0 32px;margin:0 0 30px;border-bottom:1px solid #3a4434}.lesson-content-section h2,.lesson-references h2,.lesson-all-chapters h2{font-size:21px;line-height:1.6;letter-spacing:-.3px;color:#e2e8d9;margin:0 0 17px}.lesson-content-section>p{font-size:14px;line-height:2.05;color:#b6c2aa;margin:0 0 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ui-monospace,SFMono-Regular,monospace}.lesson-all-chapters a[aria-current=page]{background:#2c3728;border-color:#78815a;color:#e0e7d4}.python-learning-page :focus-visible{outline:2px solid #e5c567;outline-offset:4px}.python-learning-page p,.python-learning-page h1,.python-learning-page h2,.python-learning-page h3{overflow-wrap:anywhere}
@media(max-width:1000px){.lesson-hero{gap:30px;grid-template-columns:minmax(0,1.35fr) minmax(260px,1fr)}.lesson-reading-layout{grid-template-columns:185px minmax(0,1fr);gap:25px}.lesson-index-card{padding:19px}.lesson-practice-grid{grid-template-columns:1fr}.lesson-practice-card{padding:18px}.lesson-practice-card h3{margin:10px 0 16px}.lesson-how>div{padding:18px}.lesson-goals{display:block}.lesson-goals ul{margin-top:12px;display:block}.lesson-goals li+li{margin-top:6px}}
@media(max-width:720px){.python-learning-page{padding-top:0}.lesson-hero{grid-template-columns:1fr;padding:21px 0 26px;gap:26px}.lesson-hero h1{font-size:31px}.lesson-hero-note{padding:22px}.lesson-lead{font-size:13px}.lesson-how{grid-template-columns:1fr;margin-bottom:35px}.lesson-how>div+div{border-left:0;border-top:1px solid #394434}.lesson-how>div{padding:16px 19px}.lesson-section-heading{display:block}.lesson-section-heading>p{margin-top:12px}.lesson-index-grid{grid-template-columns:1fr 1fr;gap:12px}.lesson-index-card{padding:17px}.lesson-index-card h3{font-size:14px}.lesson-index-card>p{font-size:11px}.lesson-index-footer{font-size:9px;gap:6px}.lesson-index-top{margin-bottom:18px}.lesson-number{font-size:24px}.lesson-bottom-note{display:block}.lesson-bottom-note .button{margin-top:20px}.lesson-breadcrumb{margin-bottom:24px}.lesson-detail-header{margin-bottom:25px}.lesson-reading-layout{grid-template-columns:1fr;gap:25px}.lesson-toc{position:static;max-height:none;overflow:visible;border:1px solid #3b4935;border-radius:9px;padding:17px 19px;background:#202a22}.lesson-toc ol{display:grid;grid-template-columns:1fr 1fr;gap:3px 17px}.lesson-toc li{margin:0}.lesson-toc a{font-size:10px}.lesson-toc .lesson-toc-back{margin-top:12px}.lesson-content-section h2{font-size:19px}.lesson-content-section>p{font-size:13px}.lesson-example>pre{padding:17px 15px;font-size:11px}.lesson-output{padding-left:15px;padding-right:15px}.lesson-output>pre{font-size:11px}.lesson-think{padding:20px}.lesson-all-chapters>div{grid-template-columns:1fr}.lesson-content-section{scroll-margin-top:85px}.lesson-references a{overflow-wrap:anywhere}}
@media(max-width:420px){.lesson-index-grid{grid-template-columns:1fr}.lesson-index-card{padding:21px}.lesson-index-top{margin-bottom:15px}.lesson-index-card h3{font-size:17px}.lesson-index-card>p{font-size:12px;margin-bottom:20px}.lesson-index-footer{font-size:10px}.lesson-toc ol{grid-template-columns:1fr}.lesson-hero h1{font-size:28px}}
@media(prefers-reduced-motion:reduce){.lesson-index-card,.lesson-practice-card{transition:none}.lesson-index-card:hover{transform:none}}

/* Keep chapter navigation independent from the global top-bar nav layout. */
.lesson-toc nav,.lesson-all-chapters{display:block;width:auto;height:auto;order:initial}.lesson-breadcrumb{height:auto;order:initial;justify-content:flex-start}