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@media(max-width:1100px){.l1-shell{grid-template-columns:180px minmax(0,1fr);gap:18px}.l1-pair{grid-template-columns:1fr}.l1-unit-grid{grid-template-columns:1fr}.l1-unit-grid a{min-height:160px}.l1-reading h1{font-size:30px}}
@media(max-width:800px){.first-course-main{padding:18px!important}.l1-shell{display:block}.l1-menu{position:static;max-height:none;margin-bottom:22px}.l1-reading{font-size:18px}.l1-art,.l1-quiz{padding:16px}.l1-reading h1,.l1-home h1{font-size:29px}.l1-lead{font-size:20px}.l1-hero{padding:23px;grid-template-columns:1fr}.l1-hero img{height:190px;grid-row:1}.l1-map{grid-template-columns:1fr 1fr}.l1-note{padding:16px;align-items:flex-start}.l1-note img{width:62px;height:76px}.l1-code pre,.l1-output pre{font-size:18px}.l1-reading h2{font-size:24px}.l1-pair{grid-template-columns:1fr}.l1-unit-grid a{padding-right:112px}.l1-unit-grid img{width:110px}.l1-bottom{font-size:17px}.l1-code,.l1-output{padding:15px}}
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@media(max-width:1200px){.l1-teaching{grid-template-columns:1fr}.l1-side-explanation .l1-note{display:flex}.l1-teaching:has(.l1-reuse) .l1-side-explanation{display:block}.l1-teaching:has(.l1-reuse) .l1-note{margin-top:18px}}

.l1-optional-tag{display:inline-block;font-size:14px;color:#6f4c97;background:#eee6f8;padding:1px 8px;border-radius:7px}.l1-optional-banner{background:#f4effb;border:1px solid #daccE9;border-radius:17px;padding:18px 22px;margin:18px 0;font-size:18px}.l1-optional-banner strong{color:#614182}.l1-optional-banner p{margin:8px 0 12px}.l1-optional-banner>a:not(.l1-primary){color:#614182;text-decoration:underline}.l1-optional-review{border-color:#dacbe9;background:#f8f4fc}