/* HTML: <div class="loader"></div> */
.loader {
    height: 50px;
    aspect-ratio: 2;
    border: 10px solid #000;
    box-sizing: border-box;
    background: radial-gradient(farthest-side,#fff 98%,#0000) left/20px 20px, radial-gradient(farthest-side,#fff 98%,#0000) left/20px 20px, radial-gradient(farthest-side,#fff 98%,#0000) center/20px 20px, radial-gradient(farthest-side,#fff 98%,#0000) right/20px 20px, #000;
    background-repeat: no-repeat;
    filter: blur(4px) contrast(10);
    animation: l14 1s infinite;
}

@keyframes l14 {
    100% {
        background-position: right,left,center,right
    }
}