Pen Settings



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.

+ add another resource


Babel includes JSX processing.

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.

+ add another resource


Add Packages

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.


Save Automatically?

If active, Pens will autosave every 30 seconds after being saved once.

Auto-Updating Preview

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

Format on Save

If enabled, your code will be formatted when you actively save your Pen. Note: your code becomes un-folded during formatting.

Editor Settings

Code Indentation

Want to change your Syntax Highlighting theme, Fonts and more?

Visit your global Editor Settings.


  <h1>The Coding Challenge</h1>   
  <!--Part 1: Code provided, Go to Part 2! -->
    <iframe src=";layout=button&amp;size=large&amp;mobile_iframe=true&amp;appId=1028195140558336&amp;width=73&amp;height=28"
        width="73" height="28" style="border:none;overflow:hidden" scrolling="no" frameborder="0" allowTransparency="true"></iframe>
    <hr />    
    <p>After your coding challenge, feel free to click on these buttons to find out more. 😁</p>
    <a class="anchor" href="/quantum-degrees/front-end-web-development" target="_blank">
      <button id="front-end" class="btn">Build Beautiful Websites with <br /> Front-end Development</button>
    <a class="anchor" href="/quantum-degrees/full-stack-web-development" target="_blank">
      <button id="full-stack" class="btn">Build Full-featured Web Apps with <br /> Frontend + Backend Development</button>
  <!--Part 2: Start coding here!!!-->
  How is a Website different from a Web App?

  <!--Part 3: Change these into paragraphs -->
  Before that, let's find out what's front-end and back-end. 

  Front-end consists of the look and feel of a website. You use HTML for the structure, CSS for styling and JavaScript to give your website a personality. You can create animations too. 

  Back-end is the server-side process which determines how the site works, updates and changes. It refers to everything you can't see, like storing information into databases and writing algorithms/ logic to interact with your database. 

  While all sites have front-end elements, a dynamic site that's constantly changing and updated in real-time requires back-end, thus showing different information to different people. This is what we call a web app. 

  However, these days you can do everything on the frontend to create a web app. But it would mean exposing sensitive code to the public and you wouldn't want to expose your proprietary code to people! This is why we still rely on back-end.

<!--Part 4: Once used, please remove-->


                /* Part 1:Pre-written code for you, please go to Part 2 */
iframe { 
  animation: glowing 1500ms infinite; 
@keyframes glowing {  
  0% { 
    background-color: #3b5998; 
    box-shadow: 0 0 3px #3b5998; 
  50% {    
    background-color: #3b5998; 
    box-shadow: 0 0 15px #3b5998; 
  100% { 
    background-color: #3b5998; 
    box-shadow: 0 0 3px #3b5998; 

h1 { 
  text-align: center;

h1, h2, h3, h4, h5, h6 { 
  font-weight: 700; 

p { 
  line-height: 150%; 

#front-end { 
  background-color: orange;
  color: white; 

#front-end:hover { 
  background-color: darkorange; color: white; 

#full-stack { 
  background-color: darkturquoise; 
  color: white; 

#full-stack:hover { 
  background-color: lightseagreen;
  color: white; 

.anchor { 
  text-decoration: none; 

.btn { 
  margin: 10px 0px; 
  padding: 10px; 
  border-radius: 10px;   
  font-size: 1em; 
  display: block; 
  width: 100%; 

/* Part 2: Add your code here */ 
section { 
  border: 1px solid lightgrey; 
  margin: 50px; 
  margin: 1em; padding: 1em;