.left{

     display: inline-block;

  width: 0;

  height: 0;

  margin-left: 2px;

  vertical-align: middle;

  border-right:4px solid;

  border-top: 4px solid transparent;

  border-bottom: 4px solid transparent;

}

.right{

     display: inline-block;

  width: 0;

  height: 0;

  margin-left: 2px;

  vertical-align: middle;

  border-left:4px solid;

  border-top: 4px solid transparent;

  border-bottom: 4px solid transparent;

}