CDN 加载失败，因为当我在浏览器中查看时样式不显示。请调查它，让我知道问题是什么，因为我很难调试。我几乎要放弃了，即将成为一个独身者。请帮忙！！！
<!DOCTYPE html>
<html lang="en">
<head>
<title>Project</title>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
</head>
<body>
<div class="jumbotron">
<h1 class="display-4">Hello, world!</h1>
<p class="lead">This is a simple hero unit, a simple jumbotron-style component for calling extra attention to featured content or information.</p>
<hr class="my-4">
<p>It uses utility classes for typography and spacing to space content out within the larger container.</p>
<a class="btn btn-primary btn-lg" href="#" role="button">Learn more</a>
</div>
</body>
</html>我在加载 CDN 引导文件时看不到任何问题。它对我有用。请检查您的浏览器设置。
它适用于 Bootstrap 4.1.3 样式表。最好在头部添加 2 个元。 上的文档 https://getbootstrap.com/docs/4.1/getting-started/introduction/
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Project</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css"
integrity="sha384-MCw98/SFnGE8fJT3GXwEOngsV7Zt27NXFoaoApmYm81iuXoPkFOJwJ8ERdknLPMO" crossorigin="anonymous">
</head>
导入“bootstrap/dist/css/bootstrap.min.css”；
导入“bootstrap/dist/js/bootstrap.bundle.min.js”；
npm i [email protected]