:root{--primary-color: #4F46E5;--primary-light: #EEF2FF;--bg-warm: #FAF8F5;--card-bg: #FFFFFF;--text-main: #1E293B;--text-muted: #64748B;--border-color: #E2E8F0;--success-color: #10B981;--danger-color: #EF4444;--warning-color: #F59E0B}body{margin:0;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;background-color:var(--bg-warm);color:var(--text-main)}.app-container{max-width:1200px;margin:0 auto;padding:20px;display:flex;flex-direction:column;min-height:100vh}.app-header{display:flex;justify-content:space-between;align-items:center;padding:16px 24px;background:var(--card-bg);border-radius:16px;box-shadow:0 4px 6px -1px #0000000d;margin-bottom:20px}.header-logo{display:flex;align-items:center;gap:12px}.logo-icon{font-size:32px}.header-logo h1{margin:0;font-size:22px;font-weight:800}.header-logo p{margin:2px 0 0;font-size:12px;color:var(--text-muted)}.header-stats{display:flex;gap:12px}.xp-badge{background:#fffbeb;border:1px solid #FDE68A;color:#d97706;padding:6px 14px;border-radius:20px;font-weight:700}.level-badge{background:var(--primary-color);color:#fff;padding:6px 14px;border-radius:20px;font-weight:700}.tab-nav{display:flex;gap:10px;margin-bottom:20px;overflow-x:auto}.tab-btn{display:flex;align-items:center;gap:8px;padding:12px 20px;background:var(--card-bg);border:1px solid var(--border-color);border-radius:12px;font-size:15px;font-weight:600;color:var(--text-muted);cursor:pointer;transition:all .2s;white-space:nowrap}.tab-btn:hover{background:var(--primary-light);color:var(--primary-color)}.tab-btn.active{background:var(--primary-color);color:#fff;border-color:var(--primary-color)}.main-content{flex:1;background:var(--card-bg);border-radius:16px;box-shadow:0 4px 6px -1px #0000000d;padding:24px}.explore-layout{display:grid;grid-template-columns:300px 1fr;gap:24px}.sidebar{border-right:1px solid var(--border-color);padding-right:20px}.search-box{display:flex;align-items:center;gap:8px;background:var(--bg-warm);border:1px solid var(--border-color);border-radius:10px;padding:8px 12px;margin-bottom:20px}.search-box input{border:none;background:transparent;outline:none;width:100%}.volume-section{margin-bottom:18px}.volume-section-title{font-size:14px;font-weight:700;margin-bottom:8px;padding-bottom:4px;border-bottom:2px solid}.topic-list{display:flex;flex-direction:column;gap:4px}.topic-item{display:flex;align-items:center;gap:6px;padding:8px 12px;background:transparent;border:none;border-radius:8px;text-align:left;font-size:14px;cursor:pointer;color:var(--text-main);position:relative}.topic-item:hover{background:var(--bg-warm)}.topic-item.active{background:var(--primary-light);color:var(--primary-color);font-weight:600}.read-dot{margin-left:auto;color:var(--success-color);font-weight:700}.topic-detail-card{display:flex;flex-direction:column;gap:20px}.detail-header{display:flex;justify-content:space-between;align-items:center}.detail-header h2{margin:0;font-size:26px;font-weight:800}.tts-btn{display:flex;align-items:center;gap:6px;background:var(--primary-light);color:var(--primary-color);border:none;padding:8px 16px;border-radius:20px;font-weight:600;cursor:pointer}.topic-definition{font-size:18px;line-height:1.6;background:#f8fafc;padding:16px;border-left:4px solid var(--primary-color);border-radius:0 12px 12px 0;margin:0}.topic-illustration{text-align:center;background:var(--bg-warm);padding:12px;border-radius:12px}.topic-illustration img{max-width:100%;max-height:260px;border-radius:8px;object-fit:cover}.illustration-caption{display:block;margin-top:8px;font-size:12px;color:var(--text-muted)}.details-list{list-style:none;padding:0;display:flex;flex-direction:column;gap:12px}.detail-bullet{display:flex;gap:12px}.bullet-num{background:var(--primary-light);color:var(--primary-color);font-weight:700;width:24px;height:24px;border-radius:50%;display:flex;align-items:center;justify-content:center;flex-shrink:0}.detail-bullet p{margin:0;font-size:15px}.read-status-box{display:flex;justify-content:center;margin-top:20px}.mark-read-btn{background:var(--success-color);color:#fff;border:none;padding:12px 24px;border-radius:12px;font-weight:700;cursor:pointer;display:flex;align-items:center;gap:8px}.status-read{color:var(--success-color);font-weight:700}.quiz-module{max-width:600px;margin:0 auto}.quiz-card{border:1px solid var(--border-color);border-radius:16px;padding:24px}.quiz-header{display:flex;justify-content:space-between;font-weight:700;margin-bottom:12px}.progress-bar-bg{height:8px;background:var(--bg-warm);border-radius:4px;overflow:hidden;margin-bottom:20px}.progress-bar-fill{height:100%;background:var(--primary-color);transition:width .3s}.quiz-question{font-size:20px;font-weight:700;margin-bottom:20px}.options-list{display:flex;flex-direction:column;gap:10px}.option-btn{display:flex;align-items:center;padding:14px;background:var(--bg-warm);border:2px solid var(--border-color);border-radius:10px;font-size:16px;font-weight:600;cursor:pointer;text-align:left}.option-btn:hover:not(:disabled){border-color:var(--primary-color)}.option-btn.correct{background:#ecfdf5;border-color:var(--success-color);color:#065f46}.option-btn.incorrect{background:#fef2f2;border-color:var(--danger-color);color:#991b1b}.option-btn.disabled{opacity:.6}.explanation-box{margin-top:20px;padding:16px;background:#f8fafc;border-radius:10px}.explanation-title{font-weight:700;margin-bottom:6px}.next-btn{margin-top:12px;background:var(--primary-color);color:#fff;border:none;padding:8px 16px;border-radius:8px;font-weight:700;cursor:pointer}.ai-creator{max-width:600px;margin:0 auto}.creator-header{display:flex;align-items:center;gap:8px}.creator-header h3{margin:0;font-size:20px}.creator-desc{color:var(--text-muted);margin-bottom:20px}.input-group{display:flex;gap:10px}.input-group input{flex:1;padding:12px;border:2px solid var(--border-color);border-radius:10px;font-size:15px}.input-group button{background:var(--primary-color);color:#fff;border:none;padding:0 20px;border-radius:10px;font-weight:700;cursor:pointer}.ai-tips{margin-top:24px}.tips-grid{display:flex;gap:8px;flex-wrap:wrap}.tip-tag{background:var(--bg-warm);border:1px solid var(--border-color);padding:6px 12px;border-radius:20px;cursor:pointer;font-size:13px}.stats-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin-bottom:24px}.stat-card{display:flex;align-items:center;gap:12px;background:var(--bg-warm);padding:16px;border-radius:12px}.stat-icon-wrapper{width:40px;height:40px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:20px}.stat-value{font-size:20px;font-weight:800;display:block}.stat-label{font-size:12px;color:var(--text-muted)}.chart-box{background:var(--bg-warm);padding:20px;border-radius:12px}.svg-chart-wrapper{height:200px}.svg-chart{width:100%;height:100%}.status-message{background:#fffbeb;border:1px solid #FDE68A;color:#d97706;padding:10px;border-radius:8px;margin-bottom:16px;display:flex;align-items:center;gap:8px;justify-content:center}.spinning{animation:spin 1s linear infinite}@keyframes spin{0%{transform:rotate(0)}to{transform:rotate(360deg)}}.empty-state{text-align:center;padding:40px;color:var(--text-muted)}.empty-icon{margin-bottom:12px;opacity:.5}