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CSS Base

Vendor Prefixing

Add External Stylesheets/Pens

Any URL's added here will be added as <link>s in order, and before the CSS in the editor. If you link to another Pen, it will include the CSS from that Pen. If the preprocessor matches, it will attempt to combine them before processing.

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You're using npm packages, so we've auto-selected Babel for you here, which we require to process imports and make it all work. If you need to use a different JavaScript preprocessor, remove the packages in the npm tab.

Add External Scripts/Pens

Any URL's added here will be added as <script>s in order, and run before the JavaScript in the editor. You can use the URL of any other Pen and it will include the JavaScript from that Pen.

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Use npm Packages

We can make npm packages available for you to use in your JavaScript. We use webpack to prepare them and make them available to import. We'll also process your JavaScript with Babel.

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Code Indentation


Save Automatically?

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Auto-Updating Preview

If enabled, the preview panel updates automatically as you code. If disabled, use the "Run" button to update.

HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <!--ORIGINAL by Another Author at
this code is a MINOR modification on the ORIGINAL-->

<div id="page">
<div class=q-a>
  <input class="toggle-box" id="identifier-1" type="checkbox">
  <label for="identifier-1">Click here to read more about HTML!</label>
  <div>As you may know, HTML (HyperText Markup Language) - is a language for web page markup. Its main goal is to translate information given in the form of readable content. Mostly, because of HTML, we see the Web as it is, we see its beauty, color and multi-functionality.
<div class=q-a>
  <input class="toggle-box" id="identifier-2" type="checkbox">
  <label for="identifier-2">Click here to read more about CSS!</label>
  <div>Cascading Style Sheets allow you to keep the color, text size, and other parameters in styles. A style is a set of formatting rules, which are applied to some parts of a document to quickly change its appearance.
              /*ORIGINAL by Another Author at*/
/* this code is a MINOR modification on the ORIGINAL */

.toggle-box {
  display: none;

.toggle-box + label {
  cursor: pointer;
  display: block;
  font-weight: bold;
  line-height: 21px;
  margin-bottom: 5px;

.toggle-box + label + div {
  display: none;
  margin-bottom: 10px;

.toggle-box:checked + label + div {
  display: block;

.toggle-box + label:before {
  background-color: #4F5150;
  -webkit-border-radius: 10px;
  -moz-border-radius: 10px;
  border-radius: 10px;
  color: #FFFFFF;
  content: "+";
  display: block;
  float: left;
  font-weight: bold;
  height: 20px;
  line-height: 20px;
  margin-right: 5px;
  text-align: center;
  width: 20px;

.toggle-box:checked + label:before {
  content: "\2212";

.q-a {
  border: 1px solid #AAA; 
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