.clouds {
    overflow: hidden;
    display: flex;
    width: 3840px;
    margin: 0 auto;
}

.clouds img {
    height: 400px;
    min-width: 300px;
    margin-left: 100px;
}

.clouds-x-slow {
    animation: clouds 270s linear infinite;
}

.clouds-xx-slow {
    animation: clouds 720s linear infinite;
}

@keyframes clouds {
    0% {
        transform: translate3d(0, 0, 0);
    }

    100% {
        transform: translate3d(-3840px, 0, 0);
        /* The image width */
    }
}

.clouds img {
    height: 100%;
    min-width: 300px;
    margin-left: 100px;
}