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#e2e8f0;border-radius:18px;margin-bottom:18px;padding:14px}.lh-lesson-shell{padding:16px}.lh-lesson-page{margin-left:0;max-width:none}.lh-lesson-card{padding:28px 22px}.lh-lesson-top{flex-direction:column;align-items:flex-start}.lh-lesson-nav-bottom{position:sticky;bottom:10px;z-index:20;box-shadow:0 12px 30px rgba(15,23,42,.12)}}@media(max-width:575.98px){.lh-lesson-shell{padding:12px}.lh-lesson-card{border-radius:20px;padding:22px 17px}.lh-lesson-card h1{font-size:31px}.lh-prose{font-size:15px}.lh-lesson-nav-bottom{padding:10px}.lh-lesson-nav-bottom .btn{font-size:13px}}