html,body {
    width:100%;
    height:100%;
    overflow: hidden;
}
#outer_cube {
    width:100%;
    height:100%;
    position:relative;
    transform-style : preserve-3d ;
    transform: perspective(400px)
}

#inner_cube {
    width:300px;
    height:300px;
    position:absolute;
    top:calc(50% - 150px);
    left:calc(50% - 150px);
    transform-style : preserve-3d;
    animation-name : rotate-full;
    animation-duration : 10s;
    animation-iteration-count: infinite;
    animation-timing-function : linear;
}

.inner_object {
    height : 20px;
    width : 20px;
    position : absolute;
    background-color: rgb(255, 255, 255,.2);
}


@keyframes rotate-full {
  0% {
    -webkit-transform: rotateY(0deg);
  }
  100% {
    -webkit-transform: rotateY(360deg);
  }
}