:root{--bg-primary: #0a0a0f;--bg-secondary: #12121a;--bg-tertiary: #1a1a24;--bg-hover: #22222e;--text-primary: #ffffff;--text-secondary: #8892a0;--text-muted: #5a6270;--accent: #74b9ff;--accent-hover: #5aa3f0;--success: #00d26a;--warning: #ffcc00;--error: #ff4757;--border: #2a2a3a;--border-light: #3a3a4a;--sidebar-width: 280px;--timeline-height: 84px;--header-height: 48px;--radius-sm: 4px;--radius-md: 8px;--radius-lg: 12px;--shadow-sm: 0 2px 4px rgba(0, 0, 0, .3);--shadow-md: 0 4px 12px rgba(0, 0, 0, .4);--shadow-lg: 0 8px 24px rgba(0, 0, 0, .5);--transition-fast: .15s ease;--transition-normal: .25s ease}*{margin:0;padding:0;box-sizing:border-box}html,body,#root{height:100%;width:100%;overflow:hidden}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,sans-serif;background:var(--bg-primary);color:var(--text-primary);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}.app{display:flex;flex-direction:column;height:100%;background:var(--bg-primary)}.app-header{height:var(--header-height);background:var(--bg-secondary);border-bottom:1px solid var(--border);display:flex;align-items:center;justify-content:space-between;padding:0 16px;-webkit-app-region:drag}.about-link{color:var(--text-secondary);text-decoration:none;font-size:13px;padding:6px 12px;border-radius:var(--radius-sm);transition:all var(--transition-fast);-webkit-app-region:no-drag}.about-link:hover{color:var(--accent);background:var(--bg-tertiary)}.app-title{font-size:14px;font-weight:600;color:var(--text-primary);display:flex;align-items:center;gap:8px}.app-title svg{width:20px;height:20px;color:var(--accent)}.app-main{display:flex;flex:1;overflow:hidden}.sidebar{width:var(--sidebar-width);background:var(--bg-secondary);border-right:1px solid var(--border);display:flex;flex-direction:column;overflow-y:auto}.sidebar-section{padding:16px;border-bottom:1px solid var(--border)}.sidebar-section-title{font-size:11px;font-weight:600;text-transform:uppercase;letter-spacing:.5px;color:var(--text-muted);margin-bottom:12px}.canvas-container{flex:1;display:flex;flex-direction:column;background:var(--bg-primary);overflow:hidden}.canvas-wrapper{flex:1;padding:16px;display:flex;align-items:center;justify-content:center;overflow:hidden}.canvas-inner{width:100%;height:100%;max-width:1920px;max-height:1080px;aspect-ratio:16 / 9;background:#000;border-radius:var(--radius-lg);overflow:hidden;box-shadow:var(--shadow-lg)}.timeline{height:var(--timeline-height);background:var(--bg-secondary);border-top:1px solid var(--border);padding:0 16px;display:flex;flex-direction:column;justify-content:center;gap:8px}.timeline-controls{display:flex;align-items:center;gap:12px}.timeline-waveform{flex:1;height:48px;background:var(--bg-tertiary);border-radius:var(--radius-md);overflow:hidden}.timeline-time{font-size:12px;font-family:Monaco,Menlo,monospace;color:var(--text-secondary);min-width:80px;text-align:center}.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:8px 16px;font-size:13px;font-weight:500;border:none;border-radius:var(--radius-md);cursor:pointer;transition:all var(--transition-fast);-webkit-app-region:no-drag}.btn-primary{background:var(--accent);color:#000}.btn-primary:hover{background:var(--accent-hover)}.btn-secondary{background:var(--bg-tertiary);color:var(--text-primary);border:1px solid var(--border)}.btn-secondary:hover{background:var(--bg-hover);border-color:var(--border-light)}.btn-icon{width:36px;height:36px;padding:0;border-radius:50%}.btn-icon.large{width:48px;height:48px}.btn-icon svg{width:18px;height:18px}.btn-icon.large svg{width:24px;height:24px}.drop-zone{border:2px dashed var(--border);border-radius:var(--radius-lg);padding:24px;text-align:center;cursor:pointer;transition:all var(--transition-fast)}.drop-zone:hover,.drop-zone.active{border-color:var(--accent);background:#74b9ff0d}.drop-zone-icon{width:40px;height:40px;margin:0 auto 12px;color:var(--text-muted)}.drop-zone-text{font-size:13px;color:var(--text-secondary)}.drop-zone-hint{font-size:11px;color:var(--text-muted);margin-top:4px}.file-info{display:flex;align-items:center;gap:12px;padding:12px;background:var(--bg-tertiary);border-radius:var(--radius-md);margin-top:8px}.file-info-icon{width:32px;height:32px;background:var(--accent);border-radius:var(--radius-sm);display:flex;align-items:center;justify-content:center}.file-info-icon svg{width:18px;height:18px;color:#000}.file-info-name{flex:1;font-size:13px;color:var(--text-primary);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.file-info-remove{width:24px;height:24px;background:transparent;border:none;color:var(--text-muted);cursor:pointer;border-radius:var(--radius-sm);display:flex;align-items:center;justify-content:center}.file-info-remove:hover{background:var(--bg-hover);color:var(--error)}.theme-selector{display:flex;gap:8px}.theme-option{flex:1;padding:12px;background:var(--bg-tertiary);border:2px solid var(--border);border-radius:var(--radius-md);cursor:pointer;transition:all var(--transition-fast);text-align:center}.theme-option:hover{border-color:var(--border-light)}.theme-option.active{border-color:var(--accent);background:#74b9ff1a}.theme-option-preview{width:100%;height:32px;border-radius:var(--radius-sm);margin-bottom:8px}.theme-option-name{font-size:12px;font-weight:500;color:var(--text-primary)}.slider-group{margin-bottom:16px}.slider-label{display:flex;justify-content:space-between;font-size:12px;color:var(--text-secondary);margin-bottom:8px}.slider-value{color:var(--text-primary);font-family:Monaco,Menlo,monospace}input[type=range]{width:100%;height:4px;background:var(--bg-tertiary);border-radius:2px;-webkit-appearance:none;appearance:none;cursor:pointer}input[type=range]::-webkit-slider-thumb{-webkit-appearance:none;width:14px;height:14px;background:var(--accent);border-radius:50%;cursor:pointer;transition:transform var(--transition-fast)}input[type=range]::-webkit-slider-thumb:hover{transform:scale(1.2)}.empty-state{display:flex;flex-direction:column;align-items:center;justify-content:center;height:100%;color:var(--text-muted);text-align:center;padding:40px}.empty-state-icon{width:64px;height:64px;margin-bottom:16px;opacity:.5}.empty-state-title{font-size:18px;font-weight:500;color:var(--text-secondary);margin-bottom:8px}.empty-state-text{font-size:13px;max-width:300px}::-webkit-scrollbar{width:8px;height:8px}::-webkit-scrollbar-track{background:transparent}::-webkit-scrollbar-thumb{background:var(--border);border-radius:4px}::-webkit-scrollbar-thumb:hover{background:var(--border-light)}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@keyframes slideUp{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.fade-in{animation:fadeIn var(--transition-normal)}.slide-up{animation:slideUp var(--transition-normal)}.canvas-container:fullscreen{background:#000;position:relative}.canvas-container:fullscreen .canvas-wrapper{padding:0;width:100%;height:100%}.canvas-container:fullscreen .canvas-inner{border-radius:0;box-shadow:none;max-width:none;max-height:none;aspect-ratio:auto}.canvas-container:fullscreen .timeline{position:absolute;bottom:0;left:0;width:100%;z-index:100;background:linear-gradient(to top,#000000e6,#0009);-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);border-top:1px solid rgba(255,255,255,.1);opacity:0;transform:translateY(100%);transition:all .3s ease}.canvas-container:fullscreen.controls-visible .timeline{opacity:1;transform:translateY(0)}.canvas-container:fullscreen .advanced-panel{display:none}.canvas-container:fullscreen canvas{width:100%!important;height:100%!important}.fullscreen-notification{position:absolute;top:40px;left:50%;transform:translate(-50%);background:#000000d9;color:#ffffffe6;padding:12px 24px;border-radius:30px;font-size:14px;font-weight:500;pointer-events:none;z-index:1000;opacity:0;animation:toastFade 4s ease forwards;box-shadow:0 4px 12px #00000080;border:1px solid rgba(255,255,255,.15);display:flex;align-items:center;gap:8px}@keyframes toastFade{0%{opacity:0;transform:translate(-50%,-20px)}10%{opacity:1;transform:translate(-50%)}75%{opacity:1;transform:translate(-50%)}to{opacity:0;transform:translate(-50%,-10px)}}