边框 css的边框
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>边框</title>
<style type="text/css">
.h{width: 500px;height: 50px;border: 2px solid red;}
.b{width: 300px; height: 200px;border:1px solid #000; border-bottom: 3px dashed #000;}
.bot{width: 100px;height: 80px; background: #333;border-radius: 19px;}
</style>
</head>
<body>
<h1 class="h">h1标题标签</h1>
<div class="b">div块</div>
<button class="bot" style="color:azure">提交</button>
</body>
</html>