Код HTML

<div class="preloader">
    <div class="loader">
        <div class="inner one"></div>
        <div class="inner two"></div>
        <div class="inner three"></div>
    </div>
</div>

Код CSS

.preloader {
    background-image: radial-gradient(circle farthest-corner at center, #3C4B57 0%, #1C262B 100%);
    position: fixed;
    width: 100%;
    height: 100%;
    left: 0;
    top: 0;
    z-index: 9999;
}
 
.loader {
    position: absolute;
    top: calc(50% - 82px);
    left: calc(50% - 82px);
    width: 164px;
    height: 164px;
    border-radius: 50%;
    perspective: 800px;
}
 
.inner {
    position: absolute;
    box-sizing: border-box;
    width: 100%;
    height: 100%;
    border-radius: 50%;
}
 
.inner.one {
    left: 0%;
    top: 0%;
    animation: rotate-one 1s linear infinite;
    border-bottom: 3px solid #EFEFFA;
}
 
.inner.two {
    right: 0%;
    top: 0%;
    animation: rotate-two 1s linear infinite;
    border-right: 3px solid #EFEFFA;
}
 
.inner.three {
    right: 0%;
    bottom: 0%;
    animation: rotate-three 1s linear infinite;
    border-top: 3px solid #EFEFFA;
}
 
@keyframes rotate-one {
    0% {
        transform: rotateX(35deg) rotateY(-45deg) rotateZ(0deg);
    }
    100% {
        transform: rotateX(35deg) rotateY(-45deg) rotateZ(360deg);
    }
}
 
@keyframes rotate-two {
    0% {
        transform: rotateX(50deg) rotateY(10deg) rotateZ(0deg);
    }
    100% {
        transform: rotateX(50deg) rotateY(10deg) rotateZ(360deg);
    }
}
 
@keyframes rotate-three {
    0% {
        transform: rotateX(35deg) rotateY(55deg) rotateZ(0deg);
    }
    100% {
        transform: rotateX(35deg) rotateY(55deg) rotateZ(360deg);
    }
}

Код JavaScript

$(window).on('load', function() {
  $('.loader').delay(1000).fadeOut();
  $('.preloader').delay(1000).fadeOut('slow');
})