要设置边框指示信息，请使用border-info类。
实现它-
<div class="one border border-info"> Information </div>
让我们看一个示例来实现border-info类-
<!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>
.one {
width: 200px;
height: 240px;
margin: 40px;
}
</style>
</head>
<body>
<div class="container">
<p>Rectangle with a border indicating information:</p>
<div class="one border border-info">Information</div>
</div>
</body>
</html>