:root{--font:"Noto Sans TC", "Noto Sans JP", system-ui, sans-serif;--bg:#fff8f0;--card-bg:#fff;--card-radius:16px;--text-primary:#2d3436;--text-secondary:#636e72;--header-height:110px}*{box-sizing:border-box;margin:0;padding:0}body{font-family:var(--font);background:var(--bg);color:var(--text-primary);-webkit-font-smoothing:antialiased;-webkit-tap-highlight-color:transparent}#app{flex-direction:column;min-height:100dvh;display:flex}.app-header{z-index:100;background:var(--bg);text-align:center;border-bottom:2px solid #eee;padding:12px 16px 0;position:sticky;top:0}.app-title{margin-bottom:8px;font-size:1.3rem;font-weight:700}.mode-tabs{gap:0;display:flex}.mode-tab{color:var(--text-secondary);border-bottom:3px solid #0000;flex:1;padding:10px 0;font-size:1.05rem;font-weight:700;text-decoration:none;transition:all .2s}.mode-tab.active{color:var(--text-primary);border-bottom-color:#ff6b6b}.app-content{flex:1;width:100%;max-width:800px;margin:0 auto;padding:16px}.category-grid{grid-template-columns:repeat(2,1fr);gap:12px;display:grid}@media (width>=600px){.category-grid{grid-template-columns:repeat(3,1fr)}}@media (width>=900px){.category-grid{grid-template-columns:repeat(4,1fr)}}.category-card{border-radius:var(--card-radius);color:#fff;flex-direction:column;justify-content:center;align-items:center;gap:6px;padding:20px 12px;text-decoration:none;transition:transform .15s,box-shadow .15s;display:flex;box-shadow:0 4px 12px #0000001a}.category-card:active{transform:scale(.96)}.category-emoji{font-size:2.2rem}.category-name{font-size:1.1rem;font-weight:700}.category-name-ja{opacity:.85;font-size:.8rem}.category-count{opacity:.75;background:#ffffff40;border-radius:10px;padding:2px 8px;font-size:.75rem}.title-bar{border-radius:var(--card-radius);color:#fff;flex-wrap:wrap;align-items:center;gap:12px;margin-bottom:12px;padding:14px 16px;display:flex}.back-btn{color:#fff;background:#fff3;border-radius:8px;padding:4px 12px;font-size:.95rem;font-weight:700;text-decoration:none}.title-text{font-size:1.2rem;font-weight:700}.title-ja{opacity:.85;font-size:.85rem}.phrase-list{flex-direction:column;gap:10px;display:flex}.phrase-card{background:var(--card-bg);border-radius:var(--card-radius);cursor:pointer;-webkit-user-select:none;user-select:none;border-left:5px solid;align-items:center;gap:12px;padding:14px;transition:transform .15s;display:flex;box-shadow:0 2px 8px #0000000f}.phrase-card:active{transform:scale(.98)}.play-btn{cursor:pointer;border:none;border-radius:50%;flex-shrink:0;justify-content:center;align-items:center;width:44px;height:44px;transition:transform .15s;display:flex}.play-btn.playing{transform:scale(1.15)}.phrase-content{flex:1;min-width:0}.phrase-japanese{font-size:1.35rem;font-weight:700;line-height:1.4}.phrase-romaji{color:var(--text-secondary);margin-top:2px;font-size:.9rem}.phrase-chinese{color:var(--text-primary);margin-top:4px;font-size:1rem}.phrase-difficulty{flex-shrink:0;font-size:.8rem}.practice-home-view{text-align:center}.practice-title{margin-bottom:4px;font-size:1.4rem}.practice-subtitle{color:var(--text-secondary);margin-bottom:16px}.select-all-btn{cursor:pointer;font-size:.95rem;font-weight:700;font-family:var(--font);background:#fff;border:2px solid #ddd;border-radius:10px;margin-bottom:12px;padding:8px 20px;display:inline-block}.practice-categories{grid-template-columns:repeat(2,1fr);gap:10px;margin-bottom:16px;display:grid}@media (width>=600px){.practice-categories{grid-template-columns:repeat(3,1fr)}}.practice-cat-card{border-radius:var(--card-radius);cursor:pointer;font-family:var(--font);background:#fff;border:3px solid #e0e0e0;flex-direction:column;align-items:center;gap:4px;padding:16px 8px;font-size:1rem;transition:all .2s;display:flex}.practice-cat-card.selected{border-color:var(--cat-color);background:color-mix(in srgb, var(--cat-color) 10%, white);box-shadow:0 0 0 2px var(--cat-color)}.cat-emoji{font-size:1.8rem}.cat-name{font-size:.95rem;font-weight:700}.difficulty-filter,.practice-mode-selector{margin-bottom:16px}.filter-label{margin-bottom:8px;font-size:.9rem;font-weight:700;display:block}.difficulty-filter .filter-btns,.practice-mode-selector .mode-btns{gap:8px;display:flex}.filter-btn,.mode-btn{cursor:pointer;font-size:.85rem;font-family:var(--font);text-align:center;background:#fff;border:2px solid #ddd;border-radius:12px;flex:1;padding:10px 8px;font-weight:700;transition:all .2s}.filter-btn.active,.mode-btn.active{background:var(--text-primary);color:#fff;border-color:var(--text-primary)}.start-practice-btn{border-radius:var(--card-radius);color:#fff;cursor:pointer;width:100%;max-width:320px;font-size:1.2rem;font-weight:700;font-family:var(--font);background:#ff6b6b;border:none;padding:16px;transition:opacity .2s,transform .15s}.start-practice-btn:disabled{opacity:.4;cursor:not-allowed}.start-practice-btn:not(:disabled):active{transform:scale(.97)}.flashcard-view{min-height:calc(100dvh - var(--header-height) - 32px);flex-direction:column;align-items:center;display:flex}.fc-progress{align-items:center;gap:10px;width:100%;margin-bottom:16px;display:flex}.fc-back{color:var(--text-primary);white-space:nowrap;font-size:.9rem;font-weight:700;text-decoration:none}.fc-progress-bar{background:#e0e0e0;border-radius:5px;flex:1;height:10px;overflow:hidden}.fc-progress-fill{background:#6bcb77;border-radius:5px;height:100%;transition:width .4s}.fc-progress-text{color:var(--text-secondary);white-space:nowrap;font-size:.8rem}.fc-card-wrapper{perspective:1000px;width:100%;max-width:380px}.fc-card{aspect-ratio:4/5;cursor:pointer;-webkit-user-select:none;user-select:none;width:100%;max-height:min(50vh,360px);position:relative}.fc-card-inner{width:100%;height:100%;transform-style:preserve-3d;transition:transform .5s;position:relative}.fc-card.flipped .fc-card-inner{transform:rotateY(180deg)}.fc-front,.fc-back{backface-visibility:hidden;background:#fff;border-radius:20px;flex-direction:column;justify-content:center;align-items:center;padding:24px;display:flex;position:absolute;inset:0;box-shadow:0 8px 30px #0000001a}.fc-back{transform:rotateY(180deg)}.fc-hint-emoji{margin-bottom:12px;font-size:2.5rem}.fc-chinese{text-align:center;font-size:1.8rem;font-weight:700;line-height:1.4}.fc-tap-hint{color:var(--text-secondary);background:#f0f0f0;border-radius:12px;margin-top:20px;padding:6px 14px;font-size:.85rem}.fc-japanese{text-align:center;margin-bottom:8px;font-size:2rem;font-weight:700;line-height:1.4}.fc-romaji{color:var(--text-secondary);margin-bottom:8px;font-size:1rem}.fc-chinese-small{margin-bottom:16px;font-size:1.1rem}.fc-play-btn{cursor:pointer;font-size:1rem;font-family:var(--font);color:#ff6b6b;background:#fff;border:2px solid #ff6b6b;border-radius:12px;padding:10px 24px;font-weight:700;transition:background .2s}.fc-play-btn:active{background:#fff0f0}.fc-overlay{opacity:0;pointer-events:none;z-index:10;border-radius:12px;padding:8px 20px;font-size:1.2rem;font-weight:700;transition:opacity .15s;position:absolute;top:20px}.fc-overlay-known{color:#155724;background:#d4edda;border:2px solid #28a745;right:16px}.fc-overlay-unknown{color:#721c24;background:#f8d7da;border:2px solid #dc3545;left:16px}.fc-swipe-hint{width:100%;max-width:380px;color:var(--text-secondary);justify-content:space-between;margin-top:12px;padding:0 8px;font-size:.8rem;display:flex}.fc-btn-row{gap:12px;width:100%;margin-top:16px;display:flex}.fc-action-btn{border-radius:var(--card-radius);cursor:pointer;font-size:1rem;font-weight:700;font-family:var(--font);border:2px solid;flex:1;padding:14px;transition:transform .15s}.fc-action-btn:active{transform:scale(.96)}.fc-btn-unknown{color:#dc3545;background:#fff5f5;border-color:#dc3545}.fc-btn-known{color:#28a745;background:#f0fff4;border-color:#28a745}.fc-complete{text-align:center;width:100%;padding:24px 0}.fc-complete-emoji{margin-bottom:12px;font-size:4rem;animation:.6s infinite alternate bounce}@keyframes bounce{0%{transform:translateY(0)}to{transform:translateY(-12px)}}.fc-complete h2{margin-bottom:8px;font-size:1.5rem}.fc-complete p{color:var(--text-secondary);margin-bottom:20px}.fc-complete-actions{flex-direction:column;align-items:center;gap:10px;margin-bottom:24px;display:flex}.fc-reset-btn{border-radius:var(--card-radius);color:#fff;cursor:pointer;font-size:1.1rem;font-weight:700;font-family:var(--font);background:#ff6b6b;border:none;padding:14px 28px}.fc-back-btn{color:var(--text-secondary);font-weight:700;text-decoration:none}.fc-stats-section{text-align:left;margin-top:12px}.fc-stats-section h3{text-align:center;margin-bottom:12px;font-size:1.1rem}.fc-stats-list{flex-direction:column;gap:8px;display:flex}.fc-stat-item{align-items:center;gap:8px;display:flex}.stat-label{text-align:right;text-overflow:ellipsis;white-space:nowrap;flex-shrink:0;width:140px;font-size:.85rem;font-weight:700;overflow:hidden}.stat-bar-bg{background:#e8e8e8;border-radius:7px;flex:1;height:14px;overflow:hidden}.stat-bar-fill{border-radius:7px;height:100%;transition:width .4s}.stat-pct{width:38px;color:var(--text-secondary);text-align:right;font-size:.8rem}.quiz-view{padding:0 16px 32px}.quiz-progress{align-items:center;gap:12px;margin-bottom:24px;display:flex}.quiz-back{flex-shrink:0}.quiz-progress-bar{background:#eee;border-radius:4px;flex:1;height:8px;overflow:hidden}.quiz-progress-fill{background:#ff6b6b;border-radius:4px;height:100%;transition:width .3s}.quiz-progress-text{color:var(--text-secondary);flex-shrink:0;font-size:.85rem}.quiz-question{text-align:center;margin-bottom:24px}.quiz-play-btn{cursor:pointer;background:#ff6b6b;border:none;border-radius:50%;width:80px;height:80px;margin-bottom:12px;font-size:2rem;transition:transform .15s}.quiz-play-btn:active{transform:scale(.9)}.quiz-chinese-prompt{margin-bottom:8px;font-size:1.8rem;font-weight:700}.quiz-prompt{color:var(--text-secondary);font-size:.9rem}.quiz-options{flex-direction:column;gap:12px;margin-bottom:16px;display:flex}.quiz-option-btn{border-radius:var(--card-radius);background:var(--card-bg);font-size:1.1rem;font-family:var(--font);cursor:pointer;text-align:left;border:2px solid #e0e0e0;padding:16px;font-weight:700;transition:all .2s}.quiz-option-btn:active:not(:disabled){transform:scale(.98)}.quiz-option-btn:disabled{cursor:default}.quiz-option-btn.correct{color:#27ae60;background:#eafaf1;border-color:#27ae60}.quiz-option-btn.wrong{color:#e74c3c;background:#fdf2f2;border-color:#e74c3c}.quiz-next-btn{border-radius:var(--card-radius);color:#fff;width:100%;font-size:1rem;font-family:var(--font);cursor:pointer;background:#ff6b6b;border:none;margin-top:12px;padding:14px;font-weight:700}.quiz-results{text-align:center}.quiz-results-header{margin-bottom:24px}.quiz-results-emoji{margin-bottom:8px;font-size:3rem}.quiz-results-header h2{margin-bottom:4px;font-size:1.8rem}.quiz-results-header p{color:var(--text-secondary)}.quiz-results-actions{flex-direction:column;gap:12px;margin-bottom:32px;display:flex}.quiz-retry-btn{border-radius:var(--card-radius);color:#fff;font-size:1rem;font-family:var(--font);cursor:pointer;background:#ff6b6b;border:none;padding:14px;font-weight:700}.quiz-back-btn{color:var(--text-secondary);font-size:.9rem;text-decoration:none}.quiz-results-breakdown h3{text-align:left;margin-bottom:12px}.quiz-breakdown-list{flex-direction:column;gap:8px;display:flex}.quiz-breakdown-item{background:var(--card-bg);text-align:left;border-radius:12px;align-items:center;gap:10px;padding:10px 12px;display:flex}.quiz-breakdown-item.correct{border-left:4px solid #27ae60}.quiz-breakdown-item.wrong{border-left:4px solid #e74c3c}.breakdown-icon{flex-shrink:0}.breakdown-japanese{flex:1;font-weight:700}.breakdown-chinese{color:var(--text-secondary);font-size:.85rem}.quiz-empty{text-align:center;color:var(--text-secondary);padding:48px 16px}.quiz-empty a{color:#ff6b6b;margin-top:16px;display:inline-block}