.next,.prev{  position: absolute;
  top: 48%;
  transform: translateY(-50%);
  width: 30px;
  height: 70px;
  z-index: 10;}
  .re {
  position: relative;width:630px;}
  .prev {
  left: 10px;
  background: url(images/arr-left.png) center center no-repeat;
  background-size: 100% 100%;}

  .next {
  right: 10px;
  background: url(images/arr-right.png) center center no-repeat;
  background-size: 100% 100%;}
  .no li{display:none;}
  .no li.on{display:block;}