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@media(min-width:1101px){.sidebar-details:not([open])>.sidebar-nav{display:block}.sidebar-details>summary{display:none}}
@media(max-width:1100px){.header-inner{gap:25px}.desktop-nav{gap:20px}.hero{gap:35px}.hero h1{font-size:3.6rem}.lesson-layout{grid-template-columns:205px minmax(0,1fr);gap:25px}.lesson-toc{display:none}.lesson-article{padding:30px}.lesson-sidebar .sidebar-summary{display:none}.sidebar-details:not([open])>.sidebar-nav{display:block}.search-button kbd{display:none}.floating-note{right:0}.hero-actions{gap:16px}.hero-actions .button{gap:15px}}
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@media(max-width:480px){.container{width:calc(100% - 28px)}.hero h1{font-size:2.9rem}.hero .intro{font-size:1rem}.hero-actions{align-items:flex-start;flex-direction:column;gap:18px}.hero-visual{margin-top:8px}.hero-grid th,.hero-grid td{padding:10px}.floating-note{padding:12px 15px;max-width:255px}.benefit-strip{gap:13px}.benefit-strip span{width:100%}.lesson-article{padding:22px 18px}.lesson-article h1{font-size:2rem}.lesson-section h2{font-size:1.35rem}.exercise{padding:18px 14px}.exercise-actions{gap:12px}.exercise-actions .button{width:100%}.lesson-row{padding:17px 14px;gap:12px}.lesson-meta{font-size:.62rem}.lesson-row h3{font-size:.9rem}.lesson-row p{font-size:.72rem}.lesson-navigation{gap:8px}.lesson-navigation a{padding:10px;font-size:.73rem}.footer-links{gap:16px}.formula-demo{gap:5px;padding:9px}.cell-label{padding:5px 7px}.header-inner{gap:9px}.brand-mark{width:27px;height:27px}.header-actions{gap:7px}.learning-goals{padding:17px}.path-info{gap:8px}.spreadsheet td,.spreadsheet th{padding:8px 10px}.reference-table{min-width:340px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{transition:none!important;animation:none!important}}
@media print{.site-header,.site-footer,.lesson-sidebar,.lesson-toc,.exercise-actions,.search-dialog,.lesson-navigation{display:none!important}body{background:white}.container{width:100%}.lesson-layout{display:block;padding:0}.lesson-article{border:0;padding:0}.lesson-section{break-inside:avoid}.exercise{break-inside:avoid}a{text-decoration:underline}h1{font-size:30pt}}