cubeRotate.css

/* Define the container div, the cube div, and a generic face */

body {
    margin: 0;
}

.container {
    width: 100%;
    height: 100%;
    position: absolute;
    perspective-origin: center;
    perspective: 500px;
    overflow: hidden;
}

.cube {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    backface-visibility: visible;
    transform-style: preserve-3d;
    animation: cubeRotate 15s linear infinite;
}

@keyframes cubeRotate {
    0% {
        transform: translate(-50%, -50%) rotateY(0deg);
    }
    100% {
        transform: translate(-50%, -50%) rotateY(360deg);
    }
}

.face {
    display: block;
    position: absolute;
    width: 100%;
    height: 100%;
    border: none;
    font-family: sans-serif;
    font-size: 60px;
    color: white;
    text-align: center;
    background: rgba(0, 0, 0, 0.3);
}