.ball {
    pointer-events: none;
    position: absolute;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: gray;
    animation: implode 1s ease-in-out;
    animation-fill-mode: both;
    opacity: .5;
}

@keyframes implode {
    100% {transform: scale(0)}
}