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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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Adding Classes

In CodePen, whatever you write in the HTML editor is what goes within the <body> tags in a basic HTML5 template. So you don't have access to higher-up elements like the <html> tag. If you want to add classes there that can affect the whole document, this is the place to do it.

About the <head>

In CodePen, whatever you write in the HTML editor is what goes within the <body> tags in a basic HTML5 template. If you need things in the <head> of the document, put that code here.

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Insecure Resource

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CSS

About CSS Preprocessors

CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

About Vendor Prefixing

To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

We offer two popular choices: Autoprefixer (which processes your CSS server-side) and -prefix-free (which applies prefixes via a script, client-side).

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JavaScript

About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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Packages

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Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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Using packages here is powered by esm.sh, which makes packages from npm not only available on a CDN, but prepares them for native JavaScript ESM usage.

All packages are different, so refer to their docs for how they work.

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HTML 

              
                <html>
<head lang="en">
    <meta charset="UTF-8">
    <title>Testimonial</title>
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.6.3/css/font-awesome.min.css" type="text/css"/>
    <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="container">
    <div class="row">
        <div class="col-md-offset-3 col-md-6">
            <div class="panel-group" id="accordion" role="tablist" aria-multiselectable="true">
                <div class="panel panel-default">
                    <div class="panel-heading" role="tab" id="headingOne">
                        <h4 class="panel-title">
                            <a class="first" role="button" data-toggle="collapse" data-parent="#accordion" href="#collapseOne" aria-expanded="true" aria-controls="collapseOne">
                                Heading-one
                                <span> </span>
                            </a>
                        </h4>
                    </div>
                    <div id="collapseOne" class="panel-collapse collapse in" role="tabpanel" aria-labelledby="headingOne">
                        <div class="panel-body">
                            <p>Lorem , iaculis ex. Nulla vitae ipsum diam. Pellentesque vitae metus vitae massa egestas posuere. Mauris ultricies vehicula tempor. Pellentesque justo turpis, blandit nec ex eu, tempus placerat diam. Morbi a felis commodo eros consectetur rhoncus sed eget lectus. Praesent non erat vehic</p>
                        </div>
                    </div>
                </div>

                <div class="panel panel-default">
                    <div class="panel-heading" role="tab" id="headingTwo">
                        <h4 class="panel-title">
                            <a class="collapsed" role="button" data-toggle="collapse" data-parent="#accordion" href="#collapseTwo" aria-expanded="false" aria-controls="collapseTwo">
                                Heading-Two
                                <span> </span>
                            </a>
                        </h4>
                    </div>
                    <div id="collapseTwo" class="panel-collapse collapse" role="tabpanel" aria-labelledby="headingTwo">
                        <div class="panel-body">
                            <p>Pellentesque justo turpis, blandit nec ex eu, tempus placerat diam. Morbi a felis commodo eros consectetur rhoncus sed eget lectus, posuere massa id, ultricies est. Pellentesque sit amet venenatis est, quis posuere ipsum.</p>
                        </div>
                    </div>
                </div>

                <div class="panel panel-default">
                    <div class="panel-heading" role="tab" id="headingThree">
                        <h4 class="panel-title">
                            <a class="collapsed last" role="button" data-toggle="collapse" data-parent="#accordion" href="#collapseThree" aria-expanded="false" aria-controls="collapseThree">
                                Heading-Three
                                <span> </span>
                            </a>
                        </h4>
                    </div>
                    <div id="collapseThree" class="panel-collapse collapse" role="tabpanel" aria-labelledby="headingThree">
                        <div class="panel-body">
                            <p>Nulla vitae ipsum diam. Pellentesque vitae metus vitae massa egestas posuere justo turpis, blandit nec ex eu, tempus placerat diam. Morbi a felis commodo eros consectetur rhoncus sed eget lectus. Praesent non erat vehicula, posuere massa id, ultricies est. Pellentesque sit amet venenatis est, quis posuere ipsum.</p>
                        </div>
                    </div>
                </div>
            </div>
        </div>
    </div>
</div>
<script type="text/javascript" src="https://code.jquery.com/jquery-1.12.0.min.js"></script>
  <script type="text/javascript"  src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
</body>
</html>
!

CSS 

              
                body{
            margin-top: 50px !important;
        }
        a:hover, a:focus{
            text-decoration: none !important;
            outline: none !important;
            
        }
        .panel-group .panel{
            background-color: #fff;
            border:none;
            box-shadow:none;
            border-radius: 10px;
            margin-bottom:11px;
        }
        .panel .panel-heading{
            padding: 0;
            border-radius:10px;
            border: none;
        }
        .panel-heading a{
            color:#fff !important;
            display: block;
            border:none;
            padding:20px 35px 20px;
            font-size: 20px;
            background-color:rgb(236, 87, 102);
            font-weight:600;
            position: relative;
            color:#fff;
            box-shadow:none;
            transition:all 0.1s ease 0;
        }
        .panel-heading a:after, .panel-heading a.collapsed:after{
            content: "\f068";
            font-family: fontawesome;
            text-align: center;
            position: absolute;
            left:-20px;
            top: 10px;
            color:#fff;
            background-color:rgb(236, 87, 102);
            border: 5px solid #fff;
            font-size: 15px;
            width: 40px;
            height:40px;
            line-height: 30px;
            border-radius: 50%;
            transition:all 0.3s ease 0s;
        }
        .panel-heading:hover a:after,
        .panel-heading:hover a.collapsed:after{
            transform:rotate(360deg);
        }
        .panel-heading a.collapsed:after{
            content: "\f067";
        }
        #accordion .panel-body{
            background-color:#Fff;
            color:#8C8C8C;
            line-height: 25px;
            padding: 10px 25px 20px 35px ;
            border-top:none;
            font-size:14px;
            position: relative;
        }
!

JS
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