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HTML

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Adding Classes

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About the <head>

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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-.

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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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HTML 

              
                <div class="col-md-6"> 
    <div class="panel-group margin_0" id="accordion1">
        <div class="panel panel-default">
            <div class="panel-heading">
                <h4 class="panel-title">
                    <a class="collapsed" data-toggle="collapse" data-parent="#accordion1" href="#collapse1">
                        <i class="rt-icon2-bubble highlight"></i>
                        Lorem Ipsum
                    </a>
                </h4>
            </div>
            <div style="height: 0px;" id="collapse1" class="panel-collapse collapse">
                <div class="panel-body">
                    Lorem ipsum dolor sit amet, consectetur adipisicing elit. Praesentium amet ea dicta neque, ut quis omnis quos nam, pariatur, minus, fugit suscipit aspernatur sint ullam quas explicabo. Alias, officiis, dolor!
                </div>
            </div>
        </div>
        <div class="panel panel-default">
            <div class="panel-heading">
                <h4 class="panel-title">
                    <a data-toggle="collapse" data-parent="#accordion1" href="#collapse2" class="collapsed">
                        <i class="rt-icon2-bubble highlight"></i>
                        Dolor Sit Amet
                    </a>
                </h4>
            </div>
            <div style="height: 0px;" id="collapse2" class="panel-collapse collapse">
                <div class="panel-body">
                    Lorem ipsum dolor sit amet, consectetur adipisicing elit. Exercitationem facere doloremque ut dolores laudantium nihil at, repudiandae est numquam fuga tempora totam sequi quidem saepe officiis sint beatae, magni fugit.
                </div>
            </div>
        </div>
        <div class="panel panel-default">
            <div class="panel-heading">
                <h4 class="panel-title">
                    <a data-toggle="collapse" data-parent="#accordion1" href="#collapse3" class="collapsed">
                        <i class="rt-icon2-bubble highlight"></i>
                        Corporis Iste
                    </a>
                </h4>
            </div>
            <div style="height: 0px;" id="collapse3" class="panel-collapse collapse">
                <div class="panel-body">
                    Lorem ipsum dolor sit amet, consectetur adipisicing elit. At nobis omnis delectus, asperiores quo obcaecati et iste corporis necessitatibus tempora aspernatur doloribus. Ut deleniti commodi dicta distinctio sit enim quidem!
                </div>
            </div>
        </div>

        <div class="panel panel-default">
            <div class="panel-heading">
                <h4 class="panel-title">
                    <a data-toggle="collapse" data-parent="#accordion1" href="#collapse4" class="">
                        <i class="rt-icon2-bubble highlight"></i>
                        Adipisicing Elit
                    </a>
                </h4>
            </div>
            <div style="" id="collapse4" class="panel-collapse collapse in">
                <div class="panel-body">
                    Lorem ipsum dolor sit amet, consectetur adipisicing elit. At nobis omnis delectus, asperiores quo obcaecati et iste corporis necessitatibus tempora aspernatur doloribus. Ut deleniti commodi dicta distinctio sit enim quidem!
                    Lorem ipsum dolor sit amet, consectetur adipisicing elit. At nobis omnis delectus, asperiores quo obcaecati et iste corporis necessitatibus tempora aspernatur doloribus. Ut deleniti commodi dicta distinctio sit enim quidem!
                    Lorem ipsum dolor sit amet, consectetur adipisicing elit. At nobis omnis delectus, asperiores quo obcaecati et iste corporis necessitatibus tempora aspernatur doloribus. Ut deleniti commodi dicta distinctio sit enim quidem!
                    Lorem ipsum dolor sit amet, consectetur adipisicing elit. At nobis omnis delectus, asperiores quo obcaecati et iste corporis necessitatibus tempora aspernatur doloribus. Ut deleniti commodi dicta distinctio sit enim quidem!                       
                </div>
            </div>
        </div>
    </div> 
</div>
!

CSS 

              
                .panel-default > .panel-heading {
  background-color: transparent;
  border: medium none;
  border-radius: 0;
  color: inherit;
  padding: 0;
  position: relative;
}    
.panel-heading .panel-title > a {
  background-color: #87C540;
  border: medium none;
  color: #ffffff;
  display: block;
  font-family: Arial,Helvetica,sans-serif;
  line-height: 28px;
  padding: 11px 65px 11px 40px;
  word-wrap: break-word;
}
    
.panel-heading .panel-title > a::after {
  bottom: 0;
  content: "▲";
  font-family: "Roboto",sans-serif;
  font-size: 20px;
  font-weight: 300;
  letter-spacing: -1px;
  line-height: 48px;
  position: absolute;
  right: 0;
  text-align: center;
  top: 0;
  width: 60px;
}  
.panel-heading .panel-title > a.collapsed::after {
  content: "▼";
}    
.panel-body{
  height:100px;
  overflow: auto;
}
!

JS
!
999px

Console