.imgLoading {
    position: relative;
    box-sizing: border-box;
    width: 100%;
    height: 100%;
    background-blend-mode: screen;
    animation: 2s infinite alternate opBack;
    margin: auto;
}

@keyframes opBack {
    0% {
        background-color: rgba(55, 55, 55, 0.2);
    }
    100% {
        background-color: rgba(205, 205, 205, 0.2);
    }
}