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.2s;text-decoration:none}.lesson-footer-link:hover{background:#38bdf81a;border-color:#38bdf866}.keyboard-hint{position:fixed;bottom:80px;left:50%;transform:translate(-50%);background:#000c;border:1px solid rgba(255,255,255,.15);border-radius:12px;padding:12px 20px;display:flex;gap:16px;align-items:center;font-size:12px;color:#ffffff80;z-index:60;backdrop-filter:blur(8px);animation:hint-fade .5s ease}.keyboard-hint kbd{background:#ffffff1a;border:1px solid rgba(255,255,255,.2);border-radius:4px;padding:2px 8px;font-size:11px;color:#ffffffb3}@keyframes hint-fade{0%{opacity:0;transform:translate(-50%) translateY(10px)}}@media(max-width:768px){.lesson-slide{padding:24px 20px}.lesson-dot-nav{display:none}.lesson-slide h1{font-size:1.4rem}}@media(min-width:769px){.lesson-slide{padding:48px 64px;align-items:center;justify-content:center}}