@-webkit-keyframes scroll {
  0% {
    -webkit-transform: translateX(0);
            transform: translateX(0);
  }
  100% {
    -webkit-transform: translateX(calc(-250px * 7));
            transform: translateX(calc(-250px * 7));
  }
}

@keyframes scroll {
  0% {
    -webkit-transform: translateX(0);
            transform: translateX(0);
  }
  100% {
    -webkit-transform: translateX(calc(-250px * 7));
            transform: translateX(calc(-250px * 7));
  }
}
.slider {
  background: white;
  box-shadow: 0 10px 20px -5px rgba(0, 0, 0, 0.125);
  height: 100px;
  margin: auto;
  overflow: hidden;
  position: relative;
  width: 100%;
}
.slider .slide-track {
  -webkit-animation: scroll 40s linear infinite;
          animation: scroll 40s linear infinite;
  display: -webkit-box;
  display: flex;
  width: calc(250px * 14);
}
.slider .slide {
  height: 100px;
  width: 250px;
}