.units-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:24px;padding:20px 0}.unit-card{background:#fff;border-radius:12px;padding:30px;text-decoration:none;color:inherit;box-shadow:0 2px 8px #0000001a;transition:all .3s ease;cursor:pointer}.unit-card:hover{transform:translateY(-4px);box-shadow:0 8px 16px #00000026}.unit-number{display:inline-block;background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;padding:8px 16px;border-radius:20px;font-size:.9rem;font-weight:600;margin-bottom:16px}.unit-card h3{font-size:1.5rem;margin-bottom:8px;color:#333}.unit-card p{color:#666;font-size:1rem}.audio-player{display:flex;align-items:center;gap:16px;padding:16px;background:#f8f9fa;border-radius:8px;transition:background .2s ease}.audio-player:hover{background:#e9ecef}.play-button{width:48px;height:48px;border-radius:50%;border:none;background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;font-size:1.2rem;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:transform .2s ease;flex-shrink:0}.play-button:hover{transform:scale(1.05)}.audio-info{flex:1;min-width:0}.audio-title{display:block;font-weight:500;margin-bottom:8px;color:#333}.progress-container{width:100%}.progress-bar{width:100%;height:6px;border-radius:3px;outline:none;-webkit-appearance:none;background:#ddd;cursor:pointer}.progress-bar::-webkit-slider-thumb{-webkit-appearance:none;width:16px;height:16px;border-radius:50%;background:#667eea;cursor:pointer}.progress-bar::-moz-range-thumb{width:16px;height:16px;border-radius:50%;background:#667eea;cursor:pointer;border:none}.time-display{display:flex;justify-content:space-between;margin-top:4px;font-size:.85rem;color:#666}.video-player{width:100%;max-width:900px;margin:0 auto}.video-element{width:100%;border-radius:12px;box-shadow:0 4px 12px #00000026}.unit-container{max-width:1200px;margin:0 auto;padding:20px}.unit-header{background:#fff;padding:30px;border-radius:12px;margin-bottom:24px;box-shadow:0 2px 8px #0000001a}.back-button{display:inline-block;color:#667eea;text-decoration:none;margin-bottom:16px;font-weight:500}.back-button:hover{text-decoration:underline}.unit-header h1{font-size:2rem;margin-bottom:8px;color:#333}.tabs{display:flex;gap:8px;margin-bottom:24px}.tabs button{padding:12px 24px;border:none;background:#fff;border-radius:8px;cursor:pointer;font-size:1rem;transition:all .3s ease}.tabs button:hover{background:#f0f0f0}.tabs button.active{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff}.tab-content{background:#fff;padding:30px;border-radius:12px;box-shadow:0 2px 8px #0000001a;min-height:400px}.content-area h2,.audio-section h3{margin-bottom:20px;color:#333}.audio-list{display:flex;flex-direction:column;gap:12px}.slides-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(180px,1fr));gap:20px;max-height:70vh;overflow-y:auto;padding:10px}.slide-thumbnail{text-decoration:none;color:inherit;transition:all .3s ease;display:block}.slide-thumbnail:hover{transform:translateY(-4px)}.slide-thumbnail:hover .thumbnail-placeholder{box-shadow:0 8px 16px #0003}.thumbnail-placeholder{background:#f5f5f5;aspect-ratio:4 / 3;border-radius:8px;display:flex;align-items:center;justify-content:center;margin-bottom:8px;overflow:hidden;position:relative;border:2px solid #e0e0e0;box-shadow:0 2px 8px #0000001a;transition:all .3s ease}.thumbnail-placeholder img{width:100%;height:100%;object-fit:cover;display:block}.thumbnail-fallback{position:absolute;top:0;left:0;width:100%;height:100%;background:linear-gradient(135deg,#667eea,#764ba2);display:flex;align-items:center;justify-content:center;color:#fff;font-size:2rem;font-weight:600}.slide-thumbnail p{text-align:center;color:#666;font-size:.9rem;font-weight:500}.audio-download-list{display:flex;flex-direction:column;gap:16px;max-height:60vh;overflow-y:auto;padding:10px}.audio-item{background:#f8f9fa;border:1px solid #e0e0e0;border-radius:8px;padding:16px;display:flex;flex-direction:column;gap:12px;transition:all .3s ease}.audio-item:hover{box-shadow:0 4px 12px #0000001a;border-color:#667eea}.audio-info{display:flex;align-items:center;gap:12px;flex-wrap:wrap}.track-number{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;padding:4px 12px;border-radius:16px;font-weight:600;font-size:.9rem}.file-name{color:#666;font-size:.9rem;font-family:monospace}.audio-actions{display:flex;align-items:center;gap:12px;flex-wrap:wrap}.audio-actions audio{flex:1;min-width:250px;height:36px}.download-button{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;padding:8px 16px;border-radius:6px;text-decoration:none;font-size:.9rem;font-weight:500;white-space:nowrap;transition:all .3s ease;display:inline-flex;align-items:center;gap:6px}.download-button:hover{transform:translateY(-2px);box-shadow:0 4px 12px #667eea66}.no-audio{text-align:center;color:#999;padding:40px;font-size:1.1rem}.toolbar{position:fixed;bottom:0;left:0;right:0;height:60px;background:linear-gradient(180deg,#2d5a4a,#1e3d32);display:flex;align-items:center;justify-content:space-between;padding:0 20px;box-shadow:0 -2px 10px #0000004d;z-index:1000}.toolbar-left,.toolbar-right{display:flex;gap:8px;align-items:center}.zoom-controls{display:flex;align-items:center;gap:6px;background:#ffffff1a;padding:4px 12px;border-radius:20px;margin-right:8px}.zoom-btn{width:36px!important;height:36px!important;font-size:1rem!important;padding:0!important}.zoom-indicator{color:#fff;font-size:.9rem;font-weight:600;min-width:45px;text-align:center}.toolbar-unit-title{color:#fff;font-size:1rem;font-weight:600;padding:8px 16px;background:#ffffff1a;border-radius:20px;margin-right:12px;white-space:nowrap}.toolbar-center{display:flex;align-items:center;gap:15px}.drawing-tools{display:flex;align-items:center;gap:0;background:#ffffff0d;padding:4px;border-radius:10px}.drawing-tools .toolbar-btn{margin:0;border-radius:6px}.toolbar-center .toolbar-btn:last-of-type{margin-right:15px}.toolbar-btn{width:45px;height:45px;background:#ffffff1a;border:2px solid rgba(255,255,255,.2);border-radius:8px;color:#fff;font-size:1.3rem;cursor:pointer;transition:all .3s ease;display:flex;align-items:center;justify-content:center}.toolbar-btn:hover{background:#fff3;transform:translateY(-2px)}.toolbar-btn.active{background:#ffc1074d;border-color:#ffc107}.nav-btn{width:50px;height:50px;background:#ffffff26;border:2px solid rgba(255,255,255,.3);border-radius:50%;color:#fff;font-size:1.2rem;cursor:pointer;transition:all .3s ease;display:flex;align-items:center;justify-content:center}.nav-btn:hover{background:#ffffff40;transform:scale(1.1)}.nav-btn:disabled{opacity:.3;cursor:not-allowed}.page-indicator{color:#fff;font-size:1.1rem;font-weight:600;min-width:80px;text-align:center;background:#0000004d;padding:8px 16px;border-radius:20px}.grid-toolbar{position:fixed;bottom:0;left:0;right:0;height:60px;background:linear-gradient(180deg,#2d5a4a,#1e3d32);box-shadow:0 -2px 10px #0000004d;z-index:1000;padding:0 20px}.grid-toolbar.edit-mode{background:linear-gradient(180deg,#4a5a2d,#3d321e);box-shadow:0 -2px 10px #ffc10780}.grid-container{display:grid;grid-template-columns:repeat(30,1fr);gap:4px;height:100%;align-items:center;max-width:100%}.grid-item{height:45px;display:flex;align-items:center;justify-content:center;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.grid-cell{height:45px;border:1px dashed rgba(255,255,255,.2);border-radius:4px;transition:all .2s ease}.grid-cell-invisible{height:45px}.grid-cell.drag-over{background:#ffc1074d;border-color:#ffc107}.grid-toolbar.edit-mode .draggable{cursor:move;opacity:.9}.grid-toolbar.edit-mode .draggable:hover{opacity:1;transform:scale(1.05)}.grid-toolbar .edit-toggle{position:absolute;right:10px;top:50%;transform:translateY(-50%);z-index:10;width:45px;height:45px}.grid-toolbar .reset-btn{position:absolute;right:60px;top:50%;transform:translateY(-50%);z-index:10;width:45px;height:45px}.edit-toggle{background:#ffc10733!important;border-color:#ffc107!important}.edit-toggle.active{background:#4caf504d!important;border-color:#4caf50!important;animation:pulse-edit 1.5s infinite}@keyframes pulse-edit{0%,to{box-shadow:0 0 10px #4caf5080}50%{box-shadow:0 0 20px #4caf50cc}}.reset-btn{background:#f4433633!important;border-color:#f44336!important}.reset-btn:hover{background:#f4433666!important}.grid-toolbar.edit-mode:before{content:"拖動按鈕到任意格子";position:absolute;top:-30px;left:50%;transform:translate(-50%);background:#ffc107e6;color:#333;padding:5px 15px;border-radius:5px;font-size:.85rem;font-weight:600;white-space:nowrap;animation:fadeIn .3s ease;z-index:10}@keyframes fadeIn{0%{opacity:0;transform:translate(-50%) translateY(5px)}to{opacity:1;transform:translate(-50%) translateY(0)}}.grid-toolbar.edit-mode .grid-container{background-image:repeating-linear-gradient(90deg,transparent,transparent calc(100% / 30 - 2px),rgba(255,255,255,.1) calc(100% / 30 - 2px),rgba(255,255,255,.1) calc(100% / 30))}.hotspot{position:absolute;cursor:pointer;transition:all .3s ease;border-radius:8px;pointer-events:auto;z-index:10}.hotspot:hover{background:#667eea33;box-shadow:0 0 0 3px #667eea66}.hotspot-default{background:#92d0500a}.hotspot-audio{background:#ffc0001a}.hotspot-video{background:#ff00001a}.inline-audio-player{position:absolute;cursor:pointer;z-index:10;pointer-events:auto}.audio-icon{width:100%;height:100%;display:flex;align-items:center;justify-content:center;background:linear-gradient(135deg,#667eea,#764ba2);border-radius:50%;font-size:1.5rem;color:#fff;box-shadow:0 4px 12px #0003;transition:all .3s ease}.audio-icon:hover{transform:scale(1.1);box-shadow:0 6px 16px #0000004d}.audio-icon.playing{animation:pulse 1.5s infinite}.audio-icon.error{background:linear-gradient(135deg,#ff6b6b,#ee5a6f)}@keyframes pulse{0%,to{box-shadow:0 4px 12px #667eea66}50%{box-shadow:0 4px 20px #667eeacc}}.audio-controls{position:absolute;top:100%;left:50%;transform:translate(-50%);margin-top:10px;background:#fffffff2;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border-radius:12px;padding:12px 16px;box-shadow:0 4px 20px #00000026;min-width:250px;z-index:100;animation:slideDown .2s ease-out}@keyframes slideDown{0%{opacity:0;transform:translate(-50%) translateY(-10px)}to{opacity:1;transform:translate(-50%) translateY(0)}}.time-display{text-align:center;font-size:.85rem;color:#333;margin-bottom:8px;font-weight:500}.progress-bar::-webkit-slider-runnable-track{width:100%;height:6px;background:linear-gradient(to right,#667eea,#764ba2);border-radius:3px}.progress-bar::-webkit-slider-thumb{-webkit-appearance:none;-moz-appearance:none;appearance:none;width:16px;height:16px;background:#667eea;border-radius:50%;cursor:pointer;margin-top:-5px;box-shadow:0 2px 6px #0003;transition:transform .2s ease}.progress-bar::-moz-range-track{width:100%;height:6px;background:linear-gradient(to right,#667eea,#764ba2);border-radius:3px}.progress-bar::-moz-range-thumb{width:16px;height:16px;background:#667eea;border:none;border-radius:50%;cursor:pointer;box-shadow:0 2px 6px #0003;transition:transform .2s ease}.volume-container{display:flex;align-items:center;gap:8px}.volume-icon{font-size:1rem}.volume-bar{flex:1;height:4px;-webkit-appearance:none;-moz-appearance:none;appearance:none;background:transparent;cursor:pointer}.volume-bar::-webkit-slider-runnable-track{width:100%;height:4px;background:#ddd;border-radius:2px}.volume-bar::-webkit-slider-thumb{-webkit-appearance:none;-moz-appearance:none;appearance:none;width:12px;height:12px;background:#667eea;border-radius:50%;cursor:pointer;margin-top:-4px;box-shadow:0 1px 4px #0003}.volume-bar::-moz-range-track{width:100%;height:4px;background:#ddd;border-radius:2px}.volume-bar::-moz-range-thumb{width:12px;height:12px;background:#667eea;border:none;border-radius:50%;cursor:pointer;box-shadow:0 1px 4px #0003}.page-audio-player{position:absolute;z-index:10;pointer-events:auto;transform:translate(-50%,-50%)}.page-audio-button{position:relative;width:90px;height:40px;background:linear-gradient(135deg,#ffa726,#ff9800);border-radius:20px;display:flex;align-items:center;padding:0 10px;gap:8px;cursor:pointer;box-shadow:0 4px 16px #ff980066;transition:all .3s ease}.page-audio-button:hover{transform:translateY(-2px);box-shadow:0 6px 20px #ff980080}.page-audio-button.playing{animation:pulse-orange 1.5s infinite}.page-audio-button.error{background:linear-gradient(135deg,#ff6b6b,#ee5a6f)}@keyframes pulse-orange{0%,to{box-shadow:0 4px 16px #ff980066}50%{box-shadow:0 4px 24px #ff9800cc}}.audio-icon{font-size:1rem;color:#fff;display:flex;align-items:center;justify-content:center}.track-number{font-size:1rem;font-weight:700;color:#333;min-width:24px}.sound-waves{display:flex;align-items:center;gap:2px;margin-left:auto}.sound-waves span{width:2px;height:10px;background:#fffc;border-radius:1px;animation:wave 1s ease-in-out infinite}.sound-waves span:nth-child(1){animation-delay:0s}.sound-waves span:nth-child(2){animation-delay:.2s}.sound-waves span:nth-child(3){animation-delay:.4s}@keyframes wave{0%,to{height:6px}50%{height:14px}}.page-audio-controls{position:absolute;background:#fffffff2;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border-radius:12px;padding:12px 16px;box-shadow:0 4px 20px #00000026;min-width:250px;max-width:300px;z-index:100;animation:slideDown .2s ease-out;pointer-events:auto}.page-audio-controls.position-bottom{top:100%;left:50%;transform:translate(-50%);margin-top:10px}.page-audio-controls.position-top{bottom:100%;left:50%;transform:translate(-50%);margin-bottom:10px}.page-audio-controls.position-right{left:100%;top:50%;transform:translateY(-50%);margin-left:10px}.page-audio-controls.position-left{right:100%;top:50%;transform:translateY(-50%);margin-right:10px}.controls-drag-handle{position:absolute;top:8px;left:8px;width:20px;height:24px;color:#999;font-size:1rem;line-height:1;cursor:move;display:flex;align-items:center;justify-content:center;-webkit-user-select:none;user-select:none;transition:color .2s ease;z-index:10;pointer-events:auto}.controls-drag-handle:hover{color:#666}.controls-drag-handle:active{color:#333;cursor:grabbing}.controls-drag-handle-corner{position:absolute;bottom:8px;right:8px;width:20px;height:24px;color:#999;font-size:1rem;line-height:1;cursor:move;display:flex;align-items:center;justify-content:center;-webkit-user-select:none;user-select:none;transition:color .2s ease;transform:rotate(90deg);z-index:10;pointer-events:auto}.controls-drag-handle-corner:hover{color:#666}.controls-drag-handle-corner:active{color:#333;cursor:grabbing}.page-audio-controls.dragging{opacity:.8;box-shadow:0 6px 30px #0000004d;cursor:grabbing}.page-audio-controls.near-boundary{box-shadow:0 4px 20px #ff980066}.close-controls-button{position:absolute;top:8px;right:8px;width:24px;height:24px;border:none;background:#0000001a;color:#666;font-size:1.5rem;line-height:1;border-radius:50%;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:all .2s ease;padding:0;font-weight:300;z-index:1}.close-controls-button:hover{background:#ff00001a;color:#f44336;transform:scale(1.1)}.close-controls-button:active{transform:scale(.95)}.controls-header{display:flex;align-items:center;gap:12px;margin-bottom:8px;margin-left:28px}.pause-play-button{width:32px;height:32px;border:none;background:linear-gradient(135deg,#ffa726,#ff9800);color:#fff;font-size:1rem;border-radius:50%;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:all .2s ease;box-shadow:0 2px 8px #ff98004d}.pause-play-button:hover{transform:scale(1.1);box-shadow:0 3px 12px #ff980080}.pause-play-button:active{transform:scale(.95)}@keyframes slideDown{0%{opacity:0;transform:translateY(-10px)}to{opacity:1;transform:translateY(0)}}.time-display{flex:1;text-align:center;font-size:.85rem;color:#333;font-weight:500}.progress-container{margin-bottom:10px}.progress-bar{width:100%;height:6px;-webkit-appearance:none;-moz-appearance:none;appearance:none;background:transparent;cursor:pointer}.progress-bar::-webkit-slider-runnable-track{width:100%;height:6px;background:linear-gradient(to right,#ffa726,#ff9800);border-radius:3px}.progress-bar::-webkit-slider-thumb{-webkit-appearance:none;-moz-appearance:none;appearance:none;width:16px;height:16px;background:#ff9800;border-radius:50%;cursor:pointer;margin-top:-5px;box-shadow:0 2px 6px #0003;transition:transform .2s ease}.progress-bar::-webkit-slider-thumb:hover{transform:scale(1.2)}.progress-bar::-moz-range-track{width:100%;height:6px;background:linear-gradient(to right,#ffa726,#ff9800);border-radius:3px}.progress-bar::-moz-range-thumb{width:16px;height:16px;background:#ff9800;border:none;border-radius:50%;cursor:pointer;box-shadow:0 2px 6px #0003;transition:transform .2s ease}.progress-bar::-moz-range-thumb:hover{transform:scale(1.2)}.volume-container{display:flex;align-items:center;gap:8px;padding:4px 30px 4px 0;position:relative;z-index:1;pointer-events:auto}.volume-icon{font-size:1rem;flex-shrink:0}.volume-bar{flex:1;max-width:150px;-webkit-appearance:none;-moz-appearance:none;appearance:none;width:100%;height:24px;background:transparent;cursor:pointer;outline:none;padding:0;margin:0}.volume-bar::-webkit-slider-runnable-track{width:100%;height:8px;background:#ddd;border-radius:4px;border:none}.volume-bar::-webkit-slider-thumb{-webkit-appearance:none;-moz-appearance:none;appearance:none;width:18px;height:18px;background:#ff9800;border-radius:50%;cursor:pointer;margin-top:-5px;box-shadow:0 2px 6px #0000004d;border:2px solid white;transition:all .15s ease}.volume-bar::-webkit-slider-thumb:hover{transform:scale(1.15);box-shadow:0 3px 8px #ff980080}.volume-bar::-webkit-slider-thumb:active{transform:scale(1.05);box-shadow:0 2px 4px #0006}.volume-bar::-moz-range-track{width:100%;height:8px;background:#ddd;border-radius:4px;border:none}.volume-bar::-moz-range-thumb{width:18px;height:18px;background:#ff9800;border:2px solid white;border-radius:50%;cursor:pointer;box-shadow:0 2px 6px #0000004d;transition:all .15s ease}.volume-bar::-moz-range-thumb:hover{transform:scale(1.15);box-shadow:0 3px 8px #ff980080}.volume-bar::-moz-range-thumb:active{transform:scale(1.05);box-shadow:0 2px 4px #0006}.volume-bar:focus{outline:none}.volume-bar::-webkit-slider-runnable-track:active{background:#ccc}.page-video-player{position:absolute;transform:translate(-50%,-50%);z-index:50}.page-video-button{background:#fff;border:2px solid #005A9C;border-radius:5px;padding:5px 10px;display:flex;align-items:center;gap:5px;cursor:pointer;box-shadow:0 4px 6px #0000001a;transition:all .2s;color:#005a9c;font-weight:700}.page-video-button:hover{transform:scale(1.05);box-shadow:0 6px 8px #00000026}.page-video-button.active{background:#005a9c;color:#fff}.video-modal-overlay{position:fixed;top:0;left:0;right:0;bottom:0;background:#000000d9;display:flex;justify-content:center;align-items:center;z-index:9999}.video-modal-content{width:90%;max-width:1200px;max-height:85vh;background:#000;border-radius:8px;overflow:hidden;position:relative;display:flex;flex-direction:column}.video-modal-header{position:absolute;top:0;left:0;right:0;padding:10px 20px;background:linear-gradient(to bottom,rgba(0,0,0,.7) 0%,transparent 100%);display:flex;justify-content:space-between;align-items:center;z-index:10;color:#fff}.video-title{display:flex;align-items:center;gap:10px;font-size:16px}.video-close-btn{background:transparent;border:none;color:#fff;font-size:24px;cursor:pointer;padding:0;line-height:1}.video-container{width:100%;aspect-ratio:16 / 9;flex:1 1 auto;min-height:0;display:flex;align-items:center;justify-content:center;background:#000;position:relative}.video-content-wrapper{position:relative;height:100%;max-width:100%;aspect-ratio:16 / 9;margin:0 auto;display:flex;align-items:center;justify-content:center}.video-content-wrapper video{width:100%;height:100%;object-fit:contain}.subtitle-box{position:absolute;background:#fffffff2;border:4px solid #FF3B5C;border-radius:12px;padding:10px 20px;box-shadow:0 4px 10px #00000026;display:flex;flex-direction:column;justify-content:center;align-items:flex-start;z-index:20;pointer-events:none;transition:all .3s ease-out}.subtitle-caption{position:absolute;top:-15px;left:-15px;background:#ff3b5c;color:#fff;font-weight:700;width:32px;height:32px;border-radius:50%;display:flex;justify-content:center;align-items:center;font-size:18px;box-shadow:0 2px 4px #0003;font-family:Arial,sans-serif;transition:all .3s ease-out}.subtitle-text{text-align:left;line-height:1.4;margin:2px 0;transition:all .3s ease-out}.subtitle-text.en{font-size:24px}.subtitle-text.zh{font-size:20px}.is-fullscreen .subtitle-box{padding:15px 30px;border-width:6px;border-radius:18px}.is-fullscreen .subtitle-caption{top:-22px;left:-22px;width:48px;height:48px;font-size:27px}.is-fullscreen .subtitle-text{margin:3px 0;line-height:1.5}.is-fullscreen .subtitle-text.en{font-size:36px}.is-fullscreen .subtitle-text.zh{font-size:30px}.role-select-modal{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);background:#fff;padding:20px;border-radius:10px;z-index:30;box-shadow:0 10px 25px 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