3D BOX.css

.boxes {
    --size: 32px;
    --duration: 800ms;
    height: calc(var(--size) * 2);
    width: calc(var(--size) * 3);
    position: relative;
    transform-style: preserve-3d;
    transform-origin: 50% 50%;
    margin-top: calc(var(--size) * 1.5 * -1);
    transform: rotateX(60deg) rotateZ(45deg) rotateY(0deg) translateZ(0px);
}
.boxes .box {
    width: var(--size);
    height: var(--size);
    top: 0;
    left: 0;
    position: absolute;
    transform-style: preserve-3d;
}
.boxes .box:nth-child(1) {
    transform: translate(100%, 0);
    -webkit-animation: box1 var(--duration) linear infinite;
    animation: box1 var(--duration) linear infinite;
}
.boxes .box:nth-child(2) {
    transform: translate(0, 100%);
    -webkit-animation: box2 var(--duration) linear infinite;
    animation: box2 var(--duration) linear infinite;
}
.boxes .box:nth-child(3) {
    transform: translate(100%, 100%);
    -webkit-animation: box3 var(--duration) linear infinite;
    animation: box3 var(--duration) linear infinite;
}
.boxes .box:nth-child(4) {
    transform: translate(200%, 0);
    -webkit-animation: box4 var(--duration) linear infinite;
    animation: box4 var(--duration) linear infinite;
}
.boxes .box > div {
    --background: #f6df5c;
    --top: auto;
    --right: auto;
    --bottom: auto;
    --left: auto;
    --translateZ: calc(var(--size) / 2);
    --rotateY: 0deg;
    --rotateX: 0deg;
    position: absolute;
    width: 100%;
    height: 100%;
    background: var(--background);
    top: var(--top);
    right: var(--right);
    bottom: var(--bottom);
    left: var(--left);
    transform: rotateY(var(--rotateY)) rotateX(var(--rotateX)) translateZ(var(--translateZ));
}
.boxes .box > div:nth-child(1) {
    --top: 0;
    --left: 0;
}
.boxes .box > div:nth-child(2) {
    --background: #ffc000;
    --right: 0;
    --rotateY: 90deg;
}
.boxes .box > div:nth-child(3) {
    --background: #f2e314;
    --rotateX: -90deg;
}
.boxes .box > div:nth-child(4) {
    --background: #f0dc001f;
    --top: 0;
    --left: 0;
    --translateZ: calc(var(--size) * 3 * -1);
}

@-webkit-keyframes box1 {
    0%, 50% {
        transform: translate(100%, 0);
    }
    100% {
        transform: translate(200%, 0);
    }
}

@keyframes box1 {
    0%, 50% {
        transform: translate(100%, 0);
    }
    100% {
        transform: translate(200%, 0);
    }
}
@-webkit-keyframes box2 {
    0% {
        transform: translate(0, 100%);
    }
    50% {
        transform: translate(0, 0);
    }
    100% {
        transform: translate(100%, 0);
    }
}
@keyframes box2 {
    0% {
        transform: translate(0, 100%);
    }
    50% {
        transform: translate(0, 0);
    }
    100% {
        transform: translate(100%, 0);
    }
}
@-webkit-keyframes box3 {
    0%, 50% {
        transform: translate(100%, 100%);
    }
    100% {
        transform: translate(0, 100%);
    }
}
@keyframes box3 {
    0%, 50% {
        transform: translate(100%, 100%);
    }
    100% {
        transform: translate(0, 100%);
    }
}
@-webkit-keyframes box4 {
    0% {
        transform: translate(200%, 0);
    }
    50% {
        transform: translate(200%, 100%);
    }
    100% {
        transform: translate(100%, 100%);
    }
}
@keyframes box4 {
    0% {
        transform: translate(200%, 0);
    }
    50% {
        transform: translate(200%, 100%);
    }
    100% {
        transform: translate(100%, 100%);
    }
}
html {
    -webkit-font-smoothing: antialiased;
}

* {
    box-sizing: border-box;
}
*:before, *:after {
    box-sizing: border-box;
}

.loader {
    min-height: 100vh;
    font-family: Roboto, Arial;
    color: white;
    display: flex;
    justify-content: center;
    align-items: center;
    background: black;
    position: fixed;
    z-index: 10000;
    top:0;
    left: 0;
    bottom: 0;
    right: 0;
}
.loader span{
    position: fixed;
    bottom:10%;
    font-size: 18px;
    color: #ffc000;
}
.l-main {
    transition:all 500ms;
  }