<!-- スライダー -->
  <div class="row">
    <h3>スライダー</h3>
    <div class="autoplay-slider">
      <div class="slide"><span>1</span></div>
      <div class="slide"><span>2</span></div>
      <div class="slide"><span>3</span></div>
      <div class="slide"><span>4</span></div>
      <div class="slide"><span>5</span></div>
      <div class="slide"><span>6</span></div>
      <div class="slide"><span>1</span></div>
      <div class="slide"><span>2</span></div>
      <div class="slide"><span>3</span></div>
      <div class="slide"><span>4</span></div>
      <div class="slide"><span>5</span></div>
      <div class="slide"><span>6</span></div>
    </div>
  </div>
  

h3 {
  font-family: sans-serif;
}

.row{
    display: -ms-grid;
    -ms-grid-columns: min-content;
}

.autoplay-slider {
  display: flex;
  min-width: 100%;
  width: min-content;
  animation: 20s linear infinite sliderAnimation;
}

.slide {
  height: 200px;
  width: 400px;
  background: #3486eb;
  border: 1px solid #000;
  margin: 20px;
  position: relative;
}
span {
  position: absolute;
  font-size: 3em;
  color: #fff;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}
@keyframes sliderAnimation {
  100% {
    transform: translateX(-50%);
  }
}