使用Bootstrap 4中的border-secondary类为元素设置灰色边框。
像下面的例子一样添加它-
<div class="mystyle border border-secondary"> </div>
我还包括了“ mystyle”类来为div设置样式-
<style>
.mystyle {
width: 250px;
height: 150px;
margin: 10px;
}
</style>让我们看一个实现border-secondary类的示例-
<!DOCTYPE html>
<html lang="en">
<head>
<title>Bootstrap Example</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.1.0/css/bootstrap.min.css">
<script src="https://cdn.staticfile.org/jquery/3.3.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.1.0/js/bootstrap.min.js"></script>
<style>
.mystyle {
width: 250px;
height: 150px;
margin: 10px;
}
</style>
</head>
<body>
<div class="container">
<h2>Shape</h2>
<div class="mystyle border border-secondary">Rectangle with gray border</div>
</div>
</body>
</html>