画三角形
可以变换位置
// <!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>三角形</title>
<style>
div{
width: 0px;
border-top: 100px solid transparent;
border-right: 100px solid transparent;
border-bottom: 100px solid transparent;
border-left: 100px solid #00f;
position:absolute;
left:300px;
top:150px;
}
</style>
</head>
<body>
<div></div>
</body>
</html>
