.ballPhysicsEngine_container {
            position: absolute;
            top: 0;
            left: 0;
            pointer-events: none;
            z-index: 9999;
        }
        .ballPhysicsEngine_shadow {
            position: absolute;
            border-radius: 50%;
            background: rgba(0,0,0,0.2);
            transition: opacity 0.1s;
            pointer-events: none;
        }
        .ballPhysicsEngine_ball {
            border-radius: 50%;
            position: relative;
            user-select: none;
            cursor: grab;
            pointer-events: all;
        }