body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; background-color: #f3f4f6; }
        .glass-panel { background: rgba(255, 255, 255, 0.95); backdrop-filter: blur(10px); }
        .loader { border: 3px solid #f3f3f3; border-top: 3px solid #3B82F6; border-radius: 50%; width: 20px; height: 20px; animation: spin 1s linear infinite; display: inline-block; }
        @keyframes spin { 0% { transform: rotate(0deg); } 100% { transform: rotate(360deg); } }
        .hidden-tab { display: none; }
        .active-tab-btn { background-color: #eff6ff; color: #1d4ed8; font-weight: 600;}
        input[type="checkbox"]:checked + label { background-color: #3b82f6; color: white; border-color: #3b82f6;}