style.css

*{
    margin: 0;
    padding: 0;
}
body{
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100%;
    min-height: 100vh;
    background: rgb(7, 1, 77);
    overflow: hidden;
}
.glow{
    position: relative;
    min-width: 750px;
    height: 750px;
    margin: -150px;
    transform-origin: right;
    animation: colorChange 6s linear infinite;
}
.glow:nth-child(even){
    transform-origin: left;
}
@keyframes colorChange{
    0%{
        filter: hue-rotate(0deg);
        transform: rotate(0deg);
    }
    100%{
        filter: hue-rotate(360deg);
        transform: rotate(360deg);
    }
}

.glow span{
    position: absolute;
    top: calc(80px * var(--i));
    left: calc(80px * var(--i));
    bottom: calc(80px * var(--i));
    right: calc(80px * var(--i));
}
.glow span:before{
    content: '';
    position: absolute;
    top: 50%;
    left: -8px;
    width: 15px;
    height: 15px;
    background: #f00;
    border-radius: 50%;
}

.glow span:nth-child(3n + 1):before{
    background: rgb(255, 0, 0);
    box-shadow: 0 0 20px rgba(255,0,0,1),
                0 0 40px rgba(255,0,0,1),
                0 0 60px rgba(255,0,0,1),
                0 0 80px rgba(255,0,0,1),
                0 0 0 8px rgba(255,0,0,.1);
}
.glow span:nth-child(3n + 2):before{
    background: rgba(255,214,0,1);
    box-shadow: 0 0 20px rgba(255,214,0,1),
                0 0 40px rgba(255,214,0,1),
                0 0 60px rgba(255,214,0,1),
                0 0 80px rgba(255,214,0,1),
                0 0 0 8px rgba(255,214,0,.1);
}
.glow span:nth-child(3n + 3):before{
    background: rgba(0,226,255,1);
    box-shadow: 0 0 20px rgba(0,226,255,1),
                0 0 40px rgba(0,226,255,1),
                0 0 60px rgba(0,226,255,1),
                0 0 80px rgba(0,226,255,1),
                0 0 0 8px rgba(0,226,255,.1);
}
.glow span:nth-child(3n + 1){
    animation: animate 4s alternate infinite;
}
.glow span:nth-child(3n + 2){
    animation: animate-reverse 13s alternate infinite;
}
.glow span:nth-child(3n + 3){
    animation: animate 7s alternate infinite;
}

@keyframes animate{
    0%{
        transform: rotate(0deg);
    }
    100%{
        transform: rotate(360deg);
    }
}
@keyframes animate-reverse{
    0%{
        transform: rotate(360deg);
    }
    100%{
        transform: rotate(0deg);
    }
}