<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<!-- 连接到css文件 -->
<!-- 绝对地址 -->
<link href="/css/button.css" rel="stylesheet" type="text/css" />
<!-- 相对地址 -->
<!-- <link href="./css/button.css" rel="stylesheet" type="text/css" /> -->
</head>
<body>
<!-- 外部样式表 outside -->
<input type="button" value="按钮1" />
<br />
<br />
<input type="button" value="按钮2" />
</body>
</html>