.loading {
    display: inline-block;
    width: var(--oi-loading-size);
    height: var(--oi-loading-size);
    border-radius: 100%;
    background-color: var(--oi-loading-color, #000);
    animation: ball-scale infinite linear 0.75s;
}

@keyframes ball-scale {
    0% {
        transform: scale(0.1);
        opacity: 1;
    }

    100% {
        transform: scale(1);
        opacity: 0;
    }
}