<span></span>
span{
display: block;
//三角形
0;
height:0;
border:5px solid transparent;
border-top-color:#000000;
//旋转动画
transition: 0.3s all;
}
span:hover{
transform: rotate(180deg);//旋转180度
}
<span></span>
span{
display: block;
//三角形
0;
height:0;
border:5px solid transparent;
border-top-color:#000000;
//旋转动画
transition: 0.3s all;
}
span:hover{
transform: rotate(180deg);//旋转180度
}