Bootstrap 4 Button .btn-outline-danger class

To set an outline on a button that indicates danger, you need to use the btn-outline-danger class in Bootstrap.

Set the outline in the <button> element −

<button type="button" class="btn btn-outline-danger">
  Danger Ahead

You can try to run the following code to implement the btn-outline-danger class −


Live Demo

<!DOCTYPE html>
<html lang="en">
    <title>Bootstrap Example</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel="stylesheet" href="">
    <script src=""></script>
    <script src=""></script>
    <h2>Danger Button</h2>
    <button type="button" class="btn btn-outline-danger">Danger Ahead</button>