Bootstrap中的模式标题
要设置Bootstrap模态的头，请使用.modal-header类。
您可以尝试运行以下代码来实现modal-header类-
示例
<!DOCTYPE html>
<html>
<head>
<title>Bootstrap Example</title>
<link rel = "stylesheet" href = "https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/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/3.3.7/js/bootstrap.min.js"></script>
</head>
<body>
<div class = "container">
<h2>Examination</h2>
<button type = "button" class = "btn btn-lg" data-toggle = "modal" data-target = "#new">Result</button>
<div class = "modal fade" id = "new" role = "dialog">
<div class = "modal-dialog">
<div class = "modal-content">
<div class = "modal-header">
<button type = "button" class="close" data-dismiss="modal">×</button>
<h4 class = "modal-title">Warning</h4>
</div>
<div class = "modal-body">
<p>If JavaScript isn't enabled in your web browser, then you may not be able to see the result.</p>
</div>
<div class = "modal-footer">
<button type = "button" class = "btn btn-primary" data-dismiss = "modal">Close</button>
</div>
</div>
</div>
</div>
</div>
</body>
</html>