.slider {
    width: 5%px;
    height: 150px;
    margin: 40px;
    overflow: hidden;
}

.slider .slide-track {
    display: flex;
    animation: scroll 40s linear infinite;
    -webkit-animation: scroll 40s linear infinite;
    width: calc(210px * 14);
}

.slider .slide {
    width: 210px;
}

.slider .slide img {
    width: 70%;
}

@keyframes scroll {
    0% {
        -webkit-transform: translateX(0);
        transform: translateX(0);
    }
    100% {
        -webkit-transform: translateX(calc(-210px * 7));
        transform: translateX(calc(-210px * 7));
    }
}