Bootstrap 4卡的bg-light类
要为Bootstrap4卡设置浅灰色背景，请使用bg-light类。
像在Bootstrap中使用其他类一样，使用“cardbg-light”-
<div class="card bg-light text-dark"> <div class="card-body">Image Editor</div> </div>
上面给出了Bootstrap卡的浅灰色背景。
让我们看一个卡片灯类的例子-
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>
</head>
<body>
<div class="container">
<h2>Web Tools</h2>
<div class="card bg-light text-dark">
<div class="card-body">Image Editor</div>
</div>
<div class="card bg-light text-dark">
<div class="card-body">Image Optimizer</div>
</div>
</div>
</body>
</html>