SOURCE

<div>
  <div class="chevron"></div>
  <div class="chevron"></div>
  <div class="chevron"></div>
</div>

body {
  display: flex;
  justify-content: center;
  align-items: center;
  position: absolute;
  width: 100%;
  height: 100%;
  background: #333;
}
.chevron{
  position: absolute;
  width: 28px;
  height: 8px;
  opacity: 0;
  transform: scale3d(0.5, 0.5, 0.5);
}
.chevron:nth-child(1) {
  animation: move 3s ease-out 1s infinite;
}
.chevron:nth-child(2) {
  animation: move 3s ease-out 2s infinite;
}
.chevron:nth-child(3) {
  animation: move 3s ease-out infinite;
}
.chevron:before,
.chevron:after{
  position: absolute;
  content : "";
  height: 100%;
  width: 50%;
  background: #fff;
  top: 0;
}
.chevron:before{
  transform: skew(0deg, 30deg);
}
.chevron:after{
  right: 0;
  transform: skew(0deg, -30deg);
}


@keyframes move {
  25% {
    opacity: 1;
  }
  33% {
    opacity: 1;
    transform: translateY(30px);
  }
  67% {
    opacity: 1;
    transform: translateY(40px);
  }
  100% {
    opacity: 0;
    transform: translateY(55px) scale3d(0.5, 0.5, 0.5);
  }
}