div::after{
content: "";
display: block;
position: absolute;
top: 50%;
right: 50rpx;
margin-top: -8rpx;
width: 14rpx;
height: 14rpx;
border-width: 2rpx 2rpx 0 0;
border-style: solid;
transform: matrix(0.71, 0.71, -0.71, 0.71, 0, 0);
}
原文：https://www.cnblogs.com/lymconch/p/13324178.html