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solid #667eea}.basics-card:hover{border-color:#667eea}.basics-card:hover .card-icon{background:linear-gradient(135deg,#667eea,#764ba2);transform:scale(1.15) rotate(5deg);box-shadow:0 10px 30px #667eea66}.character-card{border-top:6px solid #ff9800}.character-card:hover{border-color:#ff9800}.character-card:hover .card-icon{background:linear-gradient(135deg,#ff9800,#f57c00);transform:scale(1.15) rotate(5deg);box-shadow:0 10px 30px #ff980066}.pinyin-card .card-icon{width:90px;height:90px;border-radius:20px;display:flex;align-items:center;justify-content:center;font-size:2.8rem;margin-bottom:20px;background:linear-gradient(135deg,#f5f7fa,#c3cfe2);transition:all .4s cubic-bezier(.175,.885,.32,1.275);box-shadow:0 6px 20px #0000001a}.pinyin-card h3{color:#333;font-size:1.6rem;margin-bottom:12px;font-weight:700}.pinyin-card p{color:#666;font-size:1rem;line-height:1.6;margin-bottom:20px;min-height:48px}.pinyin-card 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rgba(255,255,255,.3);width:100%;display:flex;flex-direction:column;gap:5px}.example-word{font-size:1.3rem;font-weight:700}.example-meaning{font-size:.95rem;opacity:.9}.pronunciation-methods{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:25px;margin-top:20px}.method-card{background:#f8f9fa;padding:6px;border-radius:12px;border:2px solid #e9ecef;transition:all .3s ease}.method-card:hover{border-color:#2196f3;box-shadow:0 4px 12px #2196f333;transform:translateY(-3px)}.method-header{margin-bottom:20px}.method-category{font-size:1.5rem;color:#2196f3;margin-bottom:4px;font-weight:700}.method-description{color:#666;font-size:1rem;line-height:1.5}.method-sounds,.method-examples{margin-top:15px}.sounds-label,.examples-label{font-weight:700;color:#333;margin-bottom:4px;font-size:1rem}.sounds-list{display:flex;flex-wrap:wrap;gap:8px}.sound-badge{padding:6px 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24px;margin-bottom:20px;background:#fff3;border:2px solid rgba(255,255,255,.3);border-radius:10px;color:#fff;cursor:pointer;font-size:1rem;transition:all .3s ease;display:inline-flex;align-items:center;gap:8px;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);font-weight:500}.back-button:hover{background:#ffffff4d;border-color:#ffffff80;transform:translate(-5px);box-shadow:0 4px 12px #0003}@media (max-width: 768px){.alphabet-entry h2{font-size:2rem}.alphabet-cards{max-width:100%}.alphabet-card{padding:30px 20px}.alphabet-card .card-icon{width:70px;height:70px;font-size:2.2rem}.alphabet-card h3{font-size:1.4rem}}.home-page{min-height:100vh;display:flex;flex-direction:column;max-width:1200px;margin:0 auto;padding:20px}.home-header{text-align:center;color:#fff;margin-bottom:50px;padding:40px 0}.home-header h1{font-size:3rem;text-shadow:2px 2px 4px 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rotate(5deg);box-shadow:0 10px 30px #667eea66}.alphabet-card{border-top:6px solid #4caf50}.alphabet-card:hover{border-color:#4caf50}.alphabet-card:hover .card-icon{background:linear-gradient(135deg,#4caf50,#45a049);transform:scale(1.15) rotate(-5deg);box-shadow:0 10px 30px #4caf5066}.card-icon{width:100px;height:100px;border-radius:24px;display:flex;align-items:center;justify-content:center;font-size:3rem;margin-bottom:25px;background:linear-gradient(135deg,#f5f7fa,#c3cfe2);transition:all .4s cubic-bezier(.175,.885,.32,1.275);box-shadow:0 6px 20px #0000001a}.feature-card h3{color:#333;font-size:1.8rem;margin-bottom:15px;font-weight:700}.feature-card p{color:#666;font-size:1.1rem;line-height:1.7;margin-bottom:25px;min-height:50px}.card-features{display:flex;justify-content:center;gap:10px;flex-wrap:wrap;margin-bottom:20px;width:100%}.feature-tag{padding:8px 16px;background:#f0f0f0;border-radius:20px;font-size:.9rem;color:#666;font-weight:500;transition:all .3s ease}.pinyin-card .feature-tag{background:#e8eaf6;color:#667eea}.alphabet-card .feature-tag{background:#e8f5e9;color:#4caf50}.feature-card:hover .feature-tag{transform:translateY(-2px);box-shadow:0 4px 8px #0000001a}.card-arrow{position:absolute;bottom:25px;right:25px;font-size:2rem;color:#ccc;transition:all .4s ease;font-weight:700}.pinyin-card:hover .card-arrow{color:#667eea;transform:translate(8px) scale(1.2)}.alphabet-card:hover .card-arrow{color:#4caf50;transform:translate(8px) scale(1.2)}.back-to-home{padding:12px 24px;margin-bottom:20px;background:#fff3;border:2px solid rgba(255,255,255,.3);border-radius:10px;color:#fff;cursor:pointer;font-size:1rem;transition:all .3s ease;display:inline-flex;align-items:center;gap:8px;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);font-weight:500}.back-to-home:hover{background:#ffffff4d;border-color:#ffffff80;transform:translate(-5px);box-shadow:0 4px 12px #0003}.home-container{max-width:1200px;margin:0 auto;padding:20px}@media (max-width: 768px){.home-header h1{font-size:2rem}.home-header p{font-size:1.1rem}.feature-cards{grid-template-columns:1fr;gap:20px}.feature-card{padding:35px 25px}.card-icon{width:80px;height:80px;font-size:2.5rem}.feature-card h3{font-size:1.5rem}.feature-card p{font-size:1rem}}*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;background:linear-gradient(135deg,#667eea,#764ba2);min-height:100vh;min-height:100dvh;overflow-x:hidden;position:relative}#root{min-height:100vh;min-height:100dvh;position:relative}