:root{--primary: #6366f1;--primary-light: #e0e7ff;--success: #10b981;--error: #f43f5e;--warning: #f59e0b;--bg: #f8fafc;--text: #1e293b;--text-light: #64748b;--white: #ffffff}body{margin:0;background-color:var(--bg);color:var(--text);font-family:PingFang SC,Microsoft YaHei,sans-serif;-webkit-font-smoothing:antialiased}.app-container{max-width:480px;margin:0 auto;min-height:100vh;display:flex;flex-direction:column}.navbar{padding:20px;display:flex;justify-content:space-between;align-items:center}.nav-left{display:flex;align-items:center;gap:12px}.logo-icon{color:var(--primary);width:32px;height:32px}.logo-text h1{font-size:1.1rem;margin:0;font-weight:800}.cloud-status{font-size:.65rem;color:var(--text-light)}.best-score{background:var(--warning);color:#fff;padding:4px 12px;border-radius:20px;font-size:.8rem;font-weight:700;display:flex;align-items:center;gap:4px}.stage{flex:1;padding:0 16px 32px}.card{background:var(--white);border-radius:32px;padding:28px;box-shadow:0 20px 25px -5px #0000000d,0 8px 10px -6px #0000000d;min-height:520px;display:flex;flex-direction:column}.hero-visual{position:relative;width:100px;height:100px;margin:20px auto}.glow-circle{position:absolute;top:0;right:0;bottom:0;left:0;background:var(--primary-light);border-radius:50%;filter:blur(20px);opacity:.6}.book-main{width:100%;height:100%;color:var(--primary);position:relative}.sparkle-top{position:absolute;top:-10px;right:-10px;color:var(--warning);animation:pulse 2s infinite}@keyframes pulse{0%,to{transform:scale(1);opacity:1}50%{transform:scale(1.2);opacity:.7}}.subject-grid{display:flex;flex-direction:column;gap:12px;margin:30px 0}.sub-card{display:flex;align-items:center;padding:16px;border:1px solid #f1f5f9;border-radius:20px;background:#f8fafc;cursor:pointer;transition:all .2s}.sub-card:hover{border-color:var(--primary);background:var(--primary-light);transform:translate(5px)}.sub-icon{width:44px;height:44px;background:var(--white);border-radius:12px;display:flex;align-items:center;justify-content:center;font-weight:800;color:var(--primary);margin-right:16px;box-shadow:0 4px 6px -1px #0000001a}.sub-meta{flex:1;text-align:left}.sub-title{display:block;font-weight:700;font-size:1rem}.sub-desc{font-size:.75rem;color:var(--text-light)}.review-trigger{margin-top:auto;background:none;border:1px dashed #cbd5e1;padding:12px;border-radius:16px;color:var(--text-light);display:flex;align-items:center;justify-content:center;gap:8px;cursor:pointer}.study-top{display:flex;justify-content:space-between;align-items:center;margin-bottom:24px}.topic-badge{background:var(--primary-light);color:var(--primary);padding:6px 14px;border-radius:12px;font-size:.75rem;font-weight:700;display:flex;align-items:center;gap:4px}.zap-icon{color:var(--warning)}.progress-wrap{display:flex;align-items:center;gap:10px;flex:1;margin-left:20px}.progress-track{flex:1;height:8px;background:#f1f5f9;border-radius:4px;overflow:hidden}.progress-bar{height:100%;background:var(--primary);transition:width .4s cubic-bezier(.34,1.56,.64,1)}.progress-text{font-size:.75rem;font-weight:700;color:var(--text-light)}.q-header{display:flex;justify-content:space-between;gap:12px;margin-bottom:24px}.q-header h3{font-size:1.2rem;line-height:1.5;margin:0}.audio-btn{background:var(--primary-light);border:none;color:var(--primary);width:36px;height:36px;border-radius:50%;display:flex;align-items:center;justify-content:center;cursor:pointer;flex-shrink:0}.options-list{display:flex;flex-direction:column;gap:12px}.opt-item{padding:18px 20px;border:2px solid #f1f5f9;border-radius:20px;background:var(--white);text-align:left;font-size:1rem;font-weight:500;display:flex;align-items:center;gap:12px;cursor:pointer;transition:all .2s}.opt-dot{width:8px;height:8px;border-radius:50%;background:#cbd5e1}.opt-item.correct{border-color:var(--success);background:#ecfdf5;color:#065f46}.opt-item.correct .opt-dot{background:var(--success)}.opt-item.wrong{border-color:var(--error);background:#fef2f2;color:#991b1b}.opt-item.wrong .opt-dot{background:var(--error)}.opt-item.hint{border-color:var(--success);border-style:dashed}.feedback-box{margin-top:24px;padding:20px;background:#f8fafc;border-radius:20px}.status-pill{display:inline-flex;align-items:center;gap:6px;padding:4px 12px;border-radius:20px;font-size:.8rem;font-weight:700;margin-bottom:10px}.is-ok{background:#d1fae5;color:var(--success)}.is-no{background:#fee2e2;color:var(--error)}.explanation{font-size:.85rem;color:var(--text-light);line-height:1.6;margin-bottom:20px}.next-btn{width:100%;padding:16px;background:var(--primary);color:#fff;border:none;border-radius:16px;font-weight:700;cursor:pointer;box-shadow:0 10px 15px -3px #6366f14d}.loading-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#fffffff2;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);display:flex;align-items:center;justify-content:center;z-index:100}.loading-panel{text-align:center;width:80%}.loader-box{position:relative;width:70px;height:70px;margin:0 auto 24px}.loader-spin{width:100%;height:100%;color:var(--primary-light);animation:spin 1s linear infinite}.loader-logo{position:absolute;top:18px;right:18px;bottom:18px;left:18px;color:var(--primary)}@keyframes spin{0%{transform:rotate(0)}to{transform:rotate(360deg)}}.loading-bar-container{width:100%;height:4px;background:#f1f5f9;border-radius:2px;margin-top:20px;overflow:hidden}.loading-bar-fill{width:40%;height:100%;background:var(--primary);animation:loadingMove 1.5s infinite ease-in-out}@keyframes loadingMove{0%{transform:translate(-100%)}to{transform:translate(250%)}}.result-header{text-align:center;margin:40px 0}.trophy-wrap{font-size:4rem;margin-bottom:20px}.trophy-big{width:80px;height:80px;color:var(--warning)}.score-num{font-size:5rem;font-weight:900;color:var(--primary);line-height:1}.result-footer{display:flex;flex-direction:column;gap:12px}.btn-primary{padding:18px;background:var(--primary);color:#fff;border:none;border-radius:18px;font-weight:700;cursor:pointer;display:flex;align-items:center;justify-content:center;gap:10px}.btn-secondary{padding:18px;background:var(--primary-light);color:var(--primary);border:none;border-radius:18px;font-weight:700;cursor:pointer}.review-header{display:flex;align-items:center;gap:16px;margin-bottom:24px}.back-btn{background:none;border:none;color:var(--primary);font-weight:700;cursor:pointer}.wrong-list{flex:1;overflow-y:auto;padding-right:4px}.wrong-card{padding:20px;background:#f8fafc;border-radius:20px;margin-bottom:16px;border-left:4px solid var(--error)}.w-question{font-weight:700;margin-bottom:8px}.w-answer{color:var(--success);font-weight:700;font-size:.9rem;margin-bottom:8px}.w-explain{font-size:.8rem;color:var(--text-light);line-height:1.5}.empty-state{text-align:center;margin-top:100px;color:var(--text-light)}