<div class="cp_arrows">
  <div class="cp_arrow"></div>
  <div class="cp_arrow"></div>
</div>

.cp_arrows {
  position: relative;
  display: flex;
  height: 300px;/*画面いっぱいにする場合100vh*/
  justify-content: center;
  align-items: center;
}
.cp_arrows .cp_arrow {/*矢印を配置するベースの設定*/
  position: absolute;
  top: 50%;/*着地点(cp_arrowsの高さの50%)*/
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 10px;
  opacity: 0;
}
.cp_arrows .cp_arrow:first-child {
  animation: arrow-move08 2s ease-in-out infinite;
}
.cp_arrows .cp_arrow:nth-child(2)  {
  animation: arrow-move08 2s 1s ease-in-out infinite;
}
.cp_arrows .cp_arrow:before,
.cp_arrows .cp_arrow:after {/*矢印全体の設定*/
  position: absolute;
  content: '';
  top: 0;
  width: 30px;
  height: 3px;
  background: #E91E63;
}
.cp_arrows .cp_arrow:before {/*矢印左の線の位置と傾斜*/
  left: 3px;
  transform: rotate(30deg);
}
.cp_arrows .cp_arrow:after {/*矢印左の線の位置と傾斜*/
  right: 3px;
  transform: rotate(-30deg);
}
@keyframes arrow-move08 {
    0% { opacity: 0; top: 40%;/*スタート地点(cp_arrowsの高さの40%)*/}
   70% { opacity: 1;}
  100% { opacity: 0;}
}