1.运行效果如图所示

wKioL1knkVfiGYwnAAAQUGf58Mg151.png-wh_50


2.实现代码如下

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <title>进度条--层叠进度条</title>
    <!-- 最新版本的 Bootstrap 核心 CSS 文件 -->
    <link rel="stylesheet" 
    href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" 
    integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" 
    crossorigin="anonymous">

    <!-- 可选的 Bootstrap 主题文件(一般不用引入) -->
    <link rel="stylesheet" 
    href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap-theme.min.css" 
    integrity="sha384-rHyoN1iRsVXV4nD0JutlnGaslCJuC7uwjduW9SVrLvRYooPp2bWYgmgJQIXwl/Sp" 
    crossorigin="anonymous">
</head>
<body>
    <h5>正常层叠进度条</h5>
    <div class="progress">
        <div class="progress-bar progress-bar-success" style="width:20%"></div>
        <div class="progress-bar progress-bar-info" style="width:10%"></div>
        <div class="progress-bar progress-bar-warning" style="width:30%"></div>
        <div class="progress-bar progress-bar-danger" style="width:15%"></div>
    </div> 


    <script src="https://cdn.bootcss.com/jquery/3.2.1/jquery.min.js"></script>
    <!-- 最新的 Bootstrap 核心 JavaScript 文件 -->
    <script src="https://cdn.bootcss.com/bootstrap/3.3.7/js/bootstrap.min.js" 
    integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" 
    crossorigin="anonymous"></script>
</body>
</html>