.base {
    left: 20%;
    position: absolute;
    top: 20%;
    width: 9em;
    transform: rotateX(45deg) rotateZ(45deg);
    transform-style: preserve-3d;
}

.cube,
.cube:after,
.cube:before {
    content: '';
    float: left;
    height: 3em;
    position: absolute;
    width: 3em;
}

/* Top */
.cube {
    background-color: #05afd1;
    position: relative;
    transform: translateZ(2em);
    transform-style: preserve-3d;
    transition: .25s;
    box-shadow: 10em 10em 1.5em rgba(0, 0, 0, 0.1);
    animation: anim 1s infinite;
}

    .cube:after {
        background-color: #049dbc;
        transform: rotateX(-90deg) translateY(3em);
        transform-origin: 100% 100%;
    }

    .cube:before {
        background-color: #048ca7;
        transform: rotateY(90deg) translateX(3em);
        transform-origin: 100% 0;
    }

    .cube:nth-child(1) {
        animation-delay: 0.05s;
    }

    .cube:nth-child(2) {
        animation-delay: 0.1s;
    }

    .cube:nth-child(3) {
        animation-delay: 0.15s;
    }

    .cube:nth-child(4) {
        animation-delay: 0.2s;
    }

    .cube:nth-child(5) {
        animation-delay: 0.25s;
    }

    .cube:nth-child(6) {
        animation-delay: 0.3s;
    }

    .cube:nth-child(7) {
        animation-delay: 0.35s;
    }

    .cube:nth-child(8) {
        animation-delay: 0.4s;
    }

    .cube:nth-child(9) {
        animation-delay: 0.45s;
    }

@keyframes anim {
    50% {
        transform: translateZ(0.5em);
    }
}