@keyframes skeleton-shimmer{0%{background-position:-600px 0}to{background-position:600px 0}}.skeleton-page{min-height:100vh;background-color:var(--background-color, #e6e9ff);display:flex;flex-direction:column;align-items:center;padding:16px;box-sizing:border-box}.skeleton-block{background:linear-gradient(90deg,#8080801a,#80808038,#8080801a);background-size:600px 100%;animation:skeleton-shimmer 1.4s ease-in-out infinite;border-radius:10px}.skeleton-title{width:180px;height:22px;margin:12px 0 6px}.skeleton-subtitle{width:90px;height:14px;margin-bottom:20px}.skeleton-card{width:100%;max-width:500px;height:110px;margin-bottom:12px;border-radius:14px}.skeleton-course{width:100%;padding:8px;box-sizing:border-box}.skeleton-section-title{width:140px;height:18px;margin:20px 0 10px 8px}.skeleton-row{display:flex;gap:10px;overflow:hidden;padding:4px 8px}.skeleton-lesson-card{flex-shrink:0;width:120px;height:80px;border-radius:10px}:root{--text-color: #111;--background-color: #e6e9ff;--card-color: #fff;--story-lesson-color: #d00000;--flashcard-lesson-color: #fef9e6;--card-text-color: #111;--section-header-color: #000;--course-header-color: #fff;font-family:system-ui,Avenir,Helvetica,Arial,sans-serif;line-height:1.5;font-weight:400;color-scheme:light dark;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}[data-theme=dark]{--text-color: #f0f0f0;--background-color: #0b0b1a;--card-color: #1e1e30;--story-lesson-color: #ff8888;--flashcard-lesson-color: #aeaecf;--card-text-color: black;--section-header-color: #ddd;--course-header-color: #0b0b1a;--background-color: rgb(41, 44, 44)}a{font-weight:500;color:#646cff;text-decoration:inherit}a:hover{color:#535bf2}body{background-color:var(--background-color);color:var(--text-color);margin:0;min-width:320px;transition:background-color .6s ease,color .3s ease}h1{font-size:3.2em;line-height:1.1}button{border-radius:8px;border:1px solid transparent;padding:.3em .9em;font-size:1em;font-weight:500;font-family:inherit;background-color:#1a1a1a;color:#fff;cursor:pointer;transition:border-color .25s}button:hover{border-color:#646cff}button:focus,button:focus-visible{outline:4px auto -webkit-focus-ring-color}.back-btn{display:inline-flex;align-items:center;gap:6px;font-size:.9rem;color:var(--text-color);opacity:.6;background:none;border:none;cursor:pointer;padding:0;margin-bottom:28px;transition:opacity .15s}.back-btn:hover{opacity:1;border-color:transparent}