:root{--font-main:"Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;--font-accent:"Outfit", sans-serif;--bg-dark:#070a13;--text-primary:#f3f4f6;--text-secondary:#9ca3af;--text-muted:#6b7280;--primary-gradient:linear-gradient(135deg, #6366f1 0%, #a855f7 50%, #ec4899 100%);--btn-gradient:linear-gradient(135deg, #4f46e5 0%, #9333ea 100%);--success:#10b981;--error:#ef4444;--warning:#f59e0b;--info:#3b82f6;--glass-bg:#0f172a73;--glass-border:#ffffff14;--glass-blur:blur(16px);--glass-shadow:0 12px 40px 0 #00000080;--transition-smooth:all .3s cubic-bezier(.4, 0, .2, 1)}*{box-sizing:border-box;margin:0;padding:0}body{background-color:var(--bg-dark);color:var(--text-primary);font-family:var(--font-main);min-height:100vh;position:relative;overflow-x:hidden}.bg-glow{filter:blur(100px);opacity:.15;z-index:-1;pointer-events:none;border-radius:50%;position:fixed}.bg-glow-1{background:#6366f1;width:500px;height:500px;animation:12s infinite alternate floatGlow;top:-10%;right:-10%}.bg-glow-2{background:#ec4899;width:400px;height:400px;animation:15s infinite alternate-reverse floatGlow;bottom:-5%;left:-10%}.bg-glow-3{opacity:.08;background:#10b981;width:300px;height:300px;top:40%;left:30%}@keyframes floatGlow{0%{transform:translate(0)scale(1)}to{transform:translate(40px,40px)scale(1.1)}}.app-container{flex-direction:column;width:100%;max-width:760px;min-height:100vh;margin:0 auto;padding:0 16px;display:flex}.app-header{border-bottom:1px solid var(--glass-border);justify-content:space-between;align-items:center;height:72px;margin-bottom:24px;display:flex}.brand{align-items:center;gap:12px;display:flex}.brand-icon{color:#a855f7;filter:drop-shadow(0 0 6px #a855f780);width:28px;height:28px}.brand-text h1{font-family:var(--font-accent);letter-spacing:-.5px;background:var(--primary-gradient);-webkit-text-fill-color:transparent;-webkit-background-clip:text;font-size:1.1rem;font-weight:800}.brand-text span{color:var(--text-secondary);font-size:.75rem}.header-actions{gap:8px;display:flex}.icon-btn{border:1px solid var(--glass-border);color:var(--text-primary);cursor:pointer;width:40px;height:40px;transition:var(--transition-smooth);background:#ffffff0a;border-radius:10px;justify-content:center;align-items:center;display:flex;position:relative}.icon-btn:hover{background:#ffffff14;border-color:#fff3;transform:translateY(-2px)}.icon-btn svg{width:18px;height:18px}.icon-btn .badge{background:var(--error);color:#fff;border-radius:8px;justify-content:center;align-items:center;min-width:16px;height:16px;padding:0 4px;font-size:.65rem;font-weight:700;display:flex;position:absolute;top:-4px;right:-4px}.page-view{flex-direction:column;flex:1;animation:.4s ease-out fadeIn;display:none}.page-view.active{display:flex}@keyframes fadeIn{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}.view-header{margin-bottom:20px}.view-header h2{font-family:var(--font-accent);margin-bottom:6px;font-size:1.6rem;font-weight:700}.view-header p{color:var(--text-secondary);font-size:.9rem;line-height:1.5}.glass-card{background:var(--glass-bg);border:1px solid var(--glass-border);-webkit-backdrop-filter:var(--glass-blur);box-shadow:var(--glass-shadow);transition:var(--transition-smooth);border-radius:16px;padding:20px}.back-link{color:#a855f7;cursor:pointer;transition:var(--transition-smooth);background:0 0;border:none;align-items:center;gap:6px;margin-bottom:8px;font-size:.9rem;font-weight:600;display:inline-flex}.back-link:hover{color:#ec4899}.back-link svg{width:16px;height:16px}.unit-grid{grid-template-columns:1fr 1fr;gap:16px;padding-bottom:40px;display:grid}@media (width<=500px){.unit-grid{grid-template-columns:1fr}}.unit-card{cursor:pointer;position:relative;overflow:hidden}.unit-card:hover{border-color:#ffffff2e;transform:translateY(-4px);box-shadow:0 12px 30px #6366f126}.unit-card-header{justify-content:space-between;align-items:center;margin-bottom:12px;display:flex}.unit-card-header .num{font-family:var(--font-accent);background:var(--primary-gradient);-webkit-text-fill-color:transparent;-webkit-background-clip:text;font-size:1.3rem;font-weight:800}.unit-card-header .title-badge{color:var(--text-secondary);background:#ffffff0f;border-radius:6px;padding:4px 8px;font-size:.75rem}.unit-card-body h3{margin-bottom:14px;font-size:1rem;font-weight:600}.unit-card-stats{flex-direction:column;gap:6px;display:flex}.stat-bar-container{background:#ffffff0d;border-radius:3px;height:6px;overflow:hidden}.stat-bar-fill{background:var(--primary-gradient);border-radius:3px;height:100%}.stat-text-row{color:var(--text-secondary);justify-content:space-between;font-size:.75rem;display:flex}.mode-options-panel{justify-content:space-between;align-items:center;gap:16px;margin-bottom:20px;display:flex}@media (width<=500px){.mode-options-panel{flex-direction:column;align-items:stretch}}.switch-container{align-items:center;gap:12px;display:flex}.switch-label{font-size:.9rem;font-weight:500}.switch-toggle{width:46px;height:24px;display:inline-block;position:relative}.switch-toggle input{opacity:0;width:0;height:0}.slider{cursor:pointer;background-color:#ffffff1a;border-radius:34px;transition:all .4s;position:absolute;inset:0}.slider:before{content:"";background-color:#fff;border-radius:50%;width:18px;height:18px;transition:all .4s;position:absolute;bottom:3px;left:3px}input:checked+.slider{background:var(--btn-gradient)}input:checked+.slider:before{transform:translate(22px)}.unit-stats-summary{gap:24px;display:flex}.unit-stats-summary .stat-item{flex-direction:column;align-items:center;display:flex}.unit-stats-summary .stat-num{font-family:var(--font-accent);color:#fff;font-size:1.4rem;font-weight:700}.unit-stats-summary .stat-lbl{color:var(--text-secondary);font-size:.75rem}.mode-grid{flex-direction:column;gap:12px;margin-bottom:40px;display:flex}.mode-card{background:var(--glass-bg);border:1px solid var(--glass-border);-webkit-backdrop-filter:var(--glass-blur);cursor:pointer;transition:var(--transition-smooth);border-radius:14px;align-items:center;gap:16px;padding:16px;display:flex}.mode-card:hover{background:#ffffff0d;border-color:#ffffff29;transform:translate(4px)}.mode-icon-wrapper{width:48px;height:48px;color:var(--icon-color);filter:drop-shadow(0 0 6px #ffffff0d);background:#ffffff08;border:1px solid #ffffff0d;border-radius:10px;flex-shrink:0;justify-content:center;align-items:center;display:flex}.mode-icon-wrapper svg{width:22px;height:22px}.mode-info h3{margin-bottom:4px;font-size:.95rem;font-weight:600}.mode-info p{color:var(--text-secondary);font-size:.8rem}.progress-bar-container{background:#ffffff0d;border-radius:2px;height:4px;margin-bottom:24px;overflow:hidden}.progress-bar-fill{background:var(--primary-gradient);height:100%;transition:width .3s}.practice-body{flex-direction:column;flex:1;display:flex}.practice-panel{flex-direction:column;flex:1;display:none}.practice-panel.active{display:flex}#panel-flashcard{align-items:center;gap:24px}.flashcard-card-3d{perspective:1000px;cursor:pointer;width:100%;max-width:480px;height:300px}.flashcard-inner{text-align:center;width:100%;height:100%;transform-style:preserve-3d;transition:transform .6s cubic-bezier(.4,0,.2,1);position:relative}.flashcard-card-3d.flipped .flashcard-inner{transform:rotateY(180deg)}.card-face{backface-visibility:hidden;background:var(--glass-bg);border:1px solid var(--glass-border);width:100%;height:100%;box-shadow:var(--glass-shadow);-webkit-backdrop-filter:var(--glass-blur);border-radius:20px;flex-direction:column;justify-content:center;align-items:center;padding:24px;display:flex;position:absolute}.card-front{color:#fff}.card-back{transform:rotateY(180deg)}.face-header{text-transform:uppercase;letter-spacing:1.5px;color:var(--text-secondary);font-size:.75rem;position:absolute;top:16px;left:20px}.word-text{font-family:var(--font-accent);letter-spacing:-1px;background:var(--primary-gradient);-webkit-text-fill-color:transparent;filter:drop-shadow(0 2px 10px #a855f726);-webkit-background-clip:text;margin-bottom:8px;font-size:2.8rem;font-weight:800}.phonetic-container{align-items:center;gap:8px;margin-bottom:12px;display:flex}.phonetic-text{color:var(--text-secondary);font-size:1.1rem;font-family:var(--font-main)}.volume-btn{color:#a855f7;cursor:pointer;transition:var(--transition-smooth);background:0 0;border:none;align-items:center;padding:4px;display:flex}.volume-btn:hover{color:#ec4899;transform:scale(1.15)}.volume-btn svg{width:20px;height:20px}.pos-tag{border:1px solid var(--glass-border);color:var(--text-secondary);background:#ffffff0d;border-radius:6px;padding:4px 10px;font-size:.85rem;font-style:italic}.flip-hint{color:var(--text-muted);font-size:.75rem;position:absolute;bottom:16px}.chinese-text{color:#fff;margin-bottom:14px;font-size:2rem;font-weight:700}.mnemonic-section{text-align:left;background:#ffffff05;border:1px solid #ffffff0a;border-radius:10px;width:100%;margin-bottom:14px;padding:10px 14px}.mnemonic-title{color:#f59e0b;margin-bottom:4px;font-size:.75rem;font-weight:700}.mnemonic-content{color:var(--text-secondary);font-size:.85rem;line-height:1.4}.example-section{text-align:left;font-size:.85rem;line-height:1.4}.example-en{color:#fff;margin-bottom:2px;font-weight:500}.example-zh{color:var(--text-secondary)}.flashcard-actions{gap:16px;width:100%;max-width:480px;display:flex}.rate-btn{cursor:pointer;height:48px;transition:var(--transition-smooth);border:none;border-radius:12px;flex:1;font-size:.95rem;font-weight:600}.rate-need-review{color:#f87171;background:#ef444426;border:1px solid #ef44444d}.rate-need-review:hover{background:#ef444440;transform:translateY(-2px)}.rate-mastered{color:#34d399;background:#10b98126;border:1px solid #10b9814d}.rate-mastered:hover{background:#10b98140;transform:translateY(-2px)}.voice-card{text-align:center;flex-direction:column;align-items:center;gap:20px;padding:30px 20px;display:flex}.card-hint-text{color:var(--text-secondary);font-size:.8rem}.prompt-text{color:#fff;min-height:50px;font-size:1.5rem;font-weight:700;line-height:1.4}.mic-section{flex-direction:column;align-items:center;margin:10px 0;display:flex;position:relative}.mic-btn{background:var(--btn-gradient);color:#fff;cursor:pointer;z-index:2;width:72px;height:72px;transition:var(--transition-smooth);border:none;border-radius:50%;justify-content:center;align-items:center;display:flex;box-shadow:0 4px 20px #a855f766}.mic-btn svg{width:30px;height:30px}.mic-btn:active{transform:scale(.95)}.mic-status{color:var(--text-secondary);margin-top:14px;font-size:.85rem}.mic-wave{background:var(--error);opacity:0;z-index:1;pointer-events:none;border-radius:50%;width:72px;height:72px;position:absolute;top:0;left:0}.mic-wave.active{animation:1.5s ease-out infinite wavePulse}@keyframes wavePulse{0%{opacity:.4;transform:scale(1)}to{opacity:0;transform:scale(1.8)}}.feedback-container{border:1px solid var(--glass-border);text-align:left;background:#ffffff08;border-radius:12px;gap:14px;width:100%;padding:16px;animation:.3s ease-out slideUp;display:flex}@keyframes slideUp{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.feedback-icon{flex-shrink:0;width:24px;height:24px}.feedback-icon.correct{color:var(--success)}.feedback-icon.correct:before{content:"✓";font-size:1.3rem;font-weight:800}.feedback-icon.incorrect{color:var(--error)}.feedback-icon.incorrect:before{content:"✗";font-size:1.3rem;font-weight:800}.feedback-main{flex:1}.feedback-status-title{margin-bottom:6px;font-size:1rem;font-weight:700}#voice-feedback-title.correct{color:var(--success)}#voice-feedback-title.incorrect{color:var(--error)}.feedback-detail{color:var(--text-secondary);margin-bottom:4px;font-size:.85rem}.feedback-detail strong{color:#fff}.voice-fallback-input{gap:10px;width:100%;margin-top:10px;display:flex}.text-input{border:1px solid var(--glass-border);color:#fff;font-size:.9rem;font-family:var(--font-main);transition:var(--transition-smooth);background:#ffffff0d;border-radius:10px;outline:none;flex:1;padding:10px 14px}.text-input:focus{background:#ffffff14;border-color:#a855f7;box-shadow:0 0 10px #a855f726}.text-input-lg{text-align:center;letter-spacing:.5px;padding:14px 20px;font-size:1.4rem;font-weight:600}.primary-btn{background:var(--btn-gradient);color:#fff;cursor:pointer;transition:var(--transition-smooth);border:none;border-radius:10px;padding:10px 20px;font-size:.9rem;font-weight:600}.primary-btn:hover{transform:translateY(-1px);box-shadow:0 4px 15px #a855f74d}.outline-btn{border:1px solid var(--glass-border);color:#fff;cursor:pointer;transition:var(--transition-smooth);background:#ffffff0a;border-radius:10px;padding:10px 20px;font-size:.9rem;font-weight:600}.outline-btn:hover{background:#ffffff14;border-color:#fff3}.dictation-card{flex-direction:column;align-items:center;gap:20px;padding:30px 20px;display:flex}.dictation-header{text-align:center;flex-direction:column;align-items:center;gap:8px;display:flex}.volume-btn-large{color:#d8b4fe;cursor:pointer;transition:var(--transition-smooth);background:#a855f726;border:1px solid #a855f74d;border-radius:14px;align-items:center;gap:8px;padding:14px 24px;font-size:1rem;font-weight:600;display:inline-flex}.volume-btn-large svg{width:22px;height:22px}.volume-btn-large:hover{background:#a855f740;transform:translateY(-2px)}.phonetic-hint{color:var(--text-secondary);font-size:1rem}.dict-input-wrapper{width:100%}.action-row{justify-content:flex-end;gap:12px;width:100%;display:flex}#dict-feedback-title.incorrect{color:var(--error)}#dict-feedback-title.correct{color:var(--success)}.spelling-card{flex-direction:column;align-items:center;gap:20px;padding:30px 20px;display:flex}.chinese-prompt{color:#fff;font-size:1.4rem;font-weight:700}.slots-container{flex-wrap:wrap;justify-content:center;gap:8px;min-height:48px;margin:10px 0;display:flex}.letter-slot{width:36px;height:44px;font-family:var(--font-accent);color:#fff;text-transform:uppercase;transition:var(--transition-smooth);border-bottom:2px solid #fff3;justify-content:center;align-items:center;font-size:1.6rem;font-weight:700;display:flex}.letter-slot.filled{border-bottom-color:#a855f7}.letter-keyboard{flex-wrap:wrap;justify-content:center;gap:8px;width:100%;max-width:440px;margin-bottom:10px;display:flex}.key-btn{border:1px solid var(--glass-border);color:#fff;min-width:38px;height:42px;font-family:var(--font-accent);text-transform:uppercase;cursor:pointer;transition:var(--transition-smooth);background:#ffffff0f;border-radius:8px;justify-content:center;align-items:center;padding:0 10px;font-size:1.3rem;font-weight:600;display:flex;box-shadow:0 2px 4px #0003}.key-btn:hover{background:#ffffff1f;border-color:#ffffff40;transform:translateY(-2px)}.key-btn.used{opacity:.25;pointer-events:none;box-shadow:none;transform:none}.sentence-card{flex-direction:column;gap:16px;padding:24px;display:flex}.sentence-chinese{color:#fff;font-size:1.3rem;font-weight:700;line-height:1.4}.sent-input-wrapper{width:100%}.textarea-input{border:1px solid var(--glass-border);color:#fff;width:100%;height:80px;font-size:1rem;font-family:var(--font-main);resize:none;transition:var(--transition-smooth);background:#ffffff0d;border-radius:10px;outline:none;padding:12px}.textarea-input:focus{background:#ffffff14;border-color:#a855f7}.text-diff{font-family:var(--font-main);color:var(--text-secondary);background:#00000026;border-radius:6px;margin-top:4px;padding:8px 12px;line-height:1.4}.text-correct{color:#34d399;font-family:var(--font-main);background:#10b98114;border:1px solid #10b98133;border-radius:6px;margin-top:4px;padding:8px 12px;font-weight:500;line-height:1.4}.practice-footer{justify-content:space-between;margin-top:24px;padding:16px 0 40px;display:flex}.practice-footer .hidden,.hidden{display:none!important}.modal-overlay{-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);z-index:100;opacity:0;background:#05070dbf;justify-content:center;align-items:center;width:100vw;height:100vh;transition:opacity .3s;display:none;position:fixed;top:0;left:0}.modal-overlay.active{opacity:1;display:flex}.modal-window{border-radius:20px;width:100%;max-width:480px;max-height:85vh;transition:transform .3s;overflow-y:auto;transform:translateY(20px)}.modal-window-lg{max-width:680px}.modal-overlay.active .modal-window{transform:translateY(0)}.modal-header{border-bottom:1px solid var(--glass-border);justify-content:space-between;align-items:center;margin-bottom:16px;padding-bottom:14px;display:flex}.modal-header h3{font-family:var(--font-accent);background:var(--primary-gradient);-webkit-text-fill-color:transparent;-webkit-background-clip:text;font-size:1.2rem;font-weight:700}.close-modal-btn{color:var(--text-secondary);cursor:pointer;transition:var(--transition-smooth);background:0 0;border:none;font-size:1.6rem}.close-modal-btn:hover{color:#fff}.modal-body{flex-direction:column;gap:16px;display:flex}.form-group{flex-direction:column;gap:8px;display:flex}.form-group label{color:var(--text-secondary);font-size:.85rem;font-weight:600}.form-hint{color:var(--text-muted);font-size:.75rem}.settings-actions{justify-content:flex-end;gap:12px;display:flex}.divider{background:var(--glass-border);height:1px;margin:10px 0}.danger-zone{background:#ef44440d;border:1px solid #ef444440;border-radius:12px;padding:16px}.danger-zone h4{color:#f87171;margin-bottom:6px;font-size:.95rem}.danger-zone p{color:var(--text-secondary);margin-bottom:12px;font-size:.8rem}.danger-btn{background:var(--error);color:#fff;cursor:pointer;transition:var(--transition-smooth);border:none;border-radius:8px;padding:8px 16px;font-size:.85rem;font-weight:600}.danger-btn:hover{background:#dc2626}.search-bar{gap:10px;display:flex}.search-results-container{flex-direction:column;gap:12px;min-height:120px;display:flex}.empty-state{text-align:center;color:var(--text-secondary);flex-direction:column;align-items:center;padding:40px 20px;font-size:.85rem;display:flex}.mnemonic-result-card{border:1px solid var(--glass-border);background:#ffffff05;border-radius:12px;padding:16px;animation:.3s ease-out fadeIn}.result-header{border-bottom:1px solid var(--glass-border);justify-content:space-between;align-items:center;margin-bottom:10px;padding-bottom:8px;display:flex}.result-word{font-family:var(--font-accent);color:#fff;font-size:1.4rem;font-weight:800}.result-phonetic{color:var(--text-secondary);margin-left:8px;font-size:.9rem}.result-chinese{color:#10b981;font-size:1.1rem;font-weight:700}.result-detail-block{margin-bottom:10px;font-size:.85rem;line-height:1.4}.detail-title{color:#a855f7;margin-bottom:2px;font-size:.75rem;font-weight:700}.detail-content{color:var(--text-secondary)}.mistakes-unit-filter{border:1px solid var(--glass-border);background:#ffffff08;border-radius:10px;justify-content:space-between;align-items:center;margin-bottom:12px;padding:10px 16px;display:flex}.mistakes-unit-filter label{font-size:.85rem;font-weight:600}.select-input{border:1px solid var(--glass-border);color:#fff;cursor:pointer;background:#0006;border-radius:8px;outline:none;padding:6px 12px;font-size:.85rem}.mistakes-list{flex-direction:column;gap:8px;max-height:400px;display:flex;overflow-y:auto}.mistake-row{border:1px solid var(--glass-border);background:#ffffff05;border-radius:10px;justify-content:space-between;align-items:center;padding:10px 16px;display:flex}.mistake-word-info{align-items:center;gap:12px;display:flex}.mistake-word{font-family:var(--font-accent);color:#fff;font-size:1.1rem;font-weight:700}.mistake-chinese{color:var(--text-secondary);font-size:.85rem}.mistake-actions{align-items:center;gap:8px;display:flex}.remove-btn{color:#ef4444;cursor:pointer;transition:var(--transition-smooth);background:0 0;border:none;border-radius:6px;padding:6px}.remove-btn:hover{color:#f87171;background:#ef44441a}.remove-btn svg{width:18px;height:18px}