.star {
    position: fixed;
    pointer-events: none;
    width: 8px;
    height: 8px;
    background: #fff;
    border-radius: 50%;
    animation: fade 1s forwards;
    box-shadow: 0 0 10px #fff;
}

@keyframes fade {
    0% {
        opacity: 1;
        transform: scale(1);
    }
    100% {
        opacity: 0;
        transform: scale(0.2);
    }
}

.star:nth-child(3n) { background: #ff3f3f; }
.star:nth-child(3n+1) { background: #3fff3f; }
.star:nth-child(3n+2) { background: #3f3fff; }