.loader {
    width: 50px;
    height: 50px;
    --_c: no-repeat radial-gradient(farthest-side, #25b09b 92%, #0000);
    background: var(--_c) top, var(--_c) right, var(--_c) bottom, var(--_c) left;
    background-size: 12px 12px;
    animation: rotateLoader 1s linear infinite;
    transform-origin: center;
}

@keyframes rotateLoader {
    0% {
        transform: rotate(0turn);
    }

    100% {
        transform: rotate(1turn);
    }
}