:root{--purple-50: #faf5ff;--purple-100: #f3e8ff;--purple-200: #e9d5ff;--purple-300: #d8b4fe;--purple-400: #c084fc;--purple-500: #a855f7;--purple-600: #9333ea;--purple-700: #7e22ce;--purple-800: #6b21a8;--purple-900: #581c87;--gray-50: #f9fafb;--gray-100: #f3f4f6;--gray-200: #e5e7eb;--gray-300: #d1d5db;--gray-400: #9ca3af;--gray-500: #6b7280;--gray-600: #4b5563;--gray-700: #374151;--gray-800: #1f2937;--gray-900: #111827;--green-500: #22c55e;--orange-500: #f97316;--red-500: #ef4444;--radius: 12px;--radius-sm: 8px;--shadow: 0 1px 3px rgba(0,0,0,.1), 0 1px 2px rgba(0,0,0,.06);--shadow-md: 0 4px 6px rgba(0,0,0,.07), 0 2px 4px rgba(0,0,0,.06)}*{margin:0;padding:0;box-sizing:border-box}html,body,#root{height:100%;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,sans-serif;background:var(--gray-50);color:var(--gray-800);-webkit-font-smoothing:antialiased}body{max-width:480px;margin:0 auto;position:relative;background:#fff;min-height:100vh}a{text-decoration:none;color:inherit}.page{padding:16px 16px 80px;min-height:100vh}.page-title{font-size:24px;font-weight:700;margin-bottom:16px;color:var(--gray-900)}.card{background:#fff;border-radius:var(--radius);padding:16px;box-shadow:var(--shadow);margin-bottom:12px}.card-purple{background:linear-gradient(135deg,var(--purple-600),var(--purple-500));color:#fff}.btn{display:inline-flex;align-items:center;justify-content:center;padding:10px 20px;border-radius:var(--radius-sm);border:none;font-size:15px;font-weight:600;cursor:pointer;transition:all .2s}.btn-primary{background:var(--purple-600);color:#fff}.btn-primary:hover{background:var(--purple-700)}.btn-primary:active{transform:scale(.97)}.btn-outline{background:transparent;color:var(--purple-600);border:1.5px solid var(--purple-300)}.btn-outline:hover{background:var(--purple-50)}.btn-sm{padding:6px 14px;font-size:13px}.btn-block{width:100%}.tag{display:inline-block;padding:4px 10px;border-radius:20px;font-size:12px;font-weight:600}.tag-purple{background:var(--purple-100);color:var(--purple-700)}.tag-green{background:#dcfce7;color:#15803d}.bottom-nav{position:fixed;bottom:0;left:50%;transform:translate(-50%);width:100%;max-width:480px;background:#fff;border-top:1px solid var(--gray-200);display:flex;justify-content:space-around;padding:8px 0;padding-bottom:max(8px,env(safe-area-inset-bottom));z-index:100}.nav-item{display:flex;flex-direction:column;align-items:center;gap:2px;font-size:11px;color:var(--gray-400);cursor:pointer;padding:4px 12px;border:none;background:none}.nav-item.active{color:var(--purple-600)}.nav-item svg{width:24px;height:24px}@keyframes fadeIn{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}.fade-in{animation:fadeIn .3s ease-out}.word-card{background:#fff;border-radius:var(--radius);padding:24px;box-shadow:var(--shadow-md);text-align:center;min-height:200px;display:flex;flex-direction:column;justify-content:center;gap:8px}.word-card .word{font-size:28px;font-weight:700;color:var(--purple-700)}.word-card .phonetic{font-size:16px;color:var(--gray-500)}.word-card .meaning{font-size:18px;color:var(--gray-700);margin-top:4px}.word-card .example{font-size:14px;color:var(--gray-600);font-style:italic;margin-top:8px;line-height:1.5}.word-card .example-cn{font-size:13px;color:var(--gray-400)}.chat-container{display:flex;flex-direction:column;height:calc(100vh - 60px)}.chat-messages{flex:1;overflow-y:auto;padding:16px;display:flex;flex-direction:column;gap:12px}.chat-bubble{max-width:80%;padding:10px 14px;border-radius:16px;font-size:15px;line-height:1.5}.chat-bubble.ai{align-self:flex-start;background:var(--gray-100);color:var(--gray-800);border-bottom-left-radius:4px}.chat-bubble.user{align-self:flex-end;background:var(--purple-600);color:#fff;border-bottom-right-radius:4px}.chat-bubble .cn-hint{font-size:12px;opacity:.7;margin-top:4px}.chat-input-bar{display:flex;gap:8px;padding:12px 16px;border-top:1px solid var(--gray-200);background:#fff}.chat-input-bar input{flex:1;padding:10px 14px;border:1.5px solid var(--gray-200);border-radius:24px;font-size:15px;outline:none;transition:border-color .2s}.chat-input-bar input:focus{border-color:var(--purple-400)}.chat-input-bar button{padding:10px 16px;border-radius:24px;border:none;background:var(--purple-600);color:#fff;font-size:15px;font-weight:600;cursor:pointer}.calendar-grid{display:grid;grid-template-columns:repeat(7,1fr);gap:4px}.calendar-day{aspect-ratio:1;display:flex;align-items:center;justify-content:center;border-radius:6px;font-size:13px;color:var(--gray-500)}.calendar-day.checked{background:var(--purple-500);color:#fff;font-weight:600}.calendar-day.today{border:2px solid var(--purple-400);font-weight:600;color:var(--purple-600)}.calendar-day.today.checked{color:#fff}.calendar-day.empty{visibility:hidden}.calendar-weekdays{display:grid;grid-template-columns:repeat(7,1fr);gap:4px;margin-bottom:4px}.calendar-weekdays span{text-align:center;font-size:12px;color:var(--gray-400);font-weight:600}.scene-list{display:flex;flex-direction:column;gap:10px}.scene-item{display:flex;align-items:center;gap:12px;padding:14px 16px;background:#fff;border-radius:var(--radius);box-shadow:var(--shadow);cursor:pointer;transition:transform .15s;border:none;width:100%;text-align:left;font-family:inherit}.scene-item:active{transform:scale(.98)}.scene-icon{font-size:28px;width:48px;height:48px;display:flex;align-items:center;justify-content:center;background:var(--purple-50);border-radius:12px;flex-shrink:0}.scene-info{flex:1}.scene-info h3{font-size:16px;font-weight:600;color:var(--gray-800)}.scene-info p{font-size:13px;color:var(--gray-500);margin-top:2px}.stats-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:10px}.stat-card{background:#fff;border-radius:var(--radius);padding:16px;box-shadow:var(--shadow);text-align:center}.stat-card .stat-value{font-size:28px;font-weight:700;color:var(--purple-600)}.stat-card .stat-label{font-size:13px;color:var(--gray-500);margin-top:4px}.sentence-list{display:flex;flex-direction:column;gap:12px}.sentence-item{padding:12px;background:var(--purple-50);border-radius:var(--radius-sm);border-left:3px solid var(--purple-400)}.sentence-item .en{font-size:15px;font-weight:500;color:var(--gray-800);margin-bottom:4px}.sentence-item .cn{font-size:13px;color:var(--gray-500)}.role-play-line{display:flex;gap:10px;padding:10px 0}.role-play-line .speaker-tag{font-size:11px;font-weight:700;text-transform:uppercase;padding:2px 8px;border-radius:10px;flex-shrink:0;height:fit-content;margin-top:2px}.role-play-line .speaker-tag.you{background:var(--purple-100);color:var(--purple-700)}.role-play-line .speaker-tag.other{background:var(--gray-100);color:var(--gray-600)}.role-play-line .line-text{font-size:15px;color:var(--gray-800);line-height:1.5}.role-play-line .line-cn{font-size:13px;color:var(--gray-400);margin-top:2px}.back-btn{display:inline-flex;align-items:center;gap:4px;font-size:15px;color:var(--purple-600);background:none;border:none;cursor:pointer;padding:4px 0;margin-bottom:12px;font-weight:500}.speak-btn{background:none;border:none;cursor:pointer;font-size:20px;padding:4px;opacity:.7;transition:opacity .2s}.speak-btn:hover{opacity:1}.section-title{font-size:17px;font-weight:700;color:var(--gray-800);margin:20px 0 10px}.tab-bar{display:flex;gap:8px;margin-bottom:16px;overflow-x:auto;padding-bottom:4px}.tab-bar button{padding:8px 16px;border-radius:20px;border:1.5px solid var(--gray-200);background:#fff;font-size:14px;font-weight:500;color:var(--gray-600);cursor:pointer;white-space:nowrap;transition:all .2s}.tab-bar button.active{background:var(--purple-600);color:#fff;border-color:var(--purple-600)}.progress-bar{height:6px;background:var(--gray-200);border-radius:3px;overflow:hidden;margin-top:8px}.progress-bar .fill{height:100%;background:var(--purple-500);border-radius:3px;transition:width .3s ease}