.loader::before {
    content: "";
    position: absolute;
    background: #0094FF;
    top: 0;
    left: 0;
    width: 0%;
    height: 100%;
    border-radius: 30px;
    animation: moving 1s ease-in-out infinite;
;
}

@keyframes moving {
    50% {
        width: 100%;
    }

    100% {
        width: 0;
        right: 0;
        left: unset;
    }
}