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/* Circuit explanation and university material additions */
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/* Physics-first lessons and quick understanding checks */
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.lesson-nav{max-height:calc(100vh - 36px);overflow-y:auto;scrollbar-width:thin}
@media(max-width:650px){.application-box{grid-template-columns:1fr}.cause-step{grid-template-columns:28px 1fr;padding:15px 14px}.concept-check{padding:17px}}
@media(max-width:850px){.lesson-nav{max-height:none;overflow-y:hidden}}