1.triangle{
2 border-left: 5px solid transparent;
3 border-right: 5px solid transparent;
4 border-bottom: 5px solid red;
5 border-width:100px;
6}
1// css clip
2<div id="triangle"></div>
3
4#triangle {
5 background-color: #003BDE;
6 clip-path: polygon(50% 0, 100% 100%, 0 100%);
7 width: 100px;
8 height: 100px;
9}