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HTML

CSS

CSS Base

Vendor Prefixing

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Any URLs added here will be added as <link>s in order, and before the CSS in the editor. You can use the CSS from another Pen by using its URL and the proper URL extension.

+ add another resource

JavaScript

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

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.

Behavior

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Editor Settings

Code Indentation

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HTML

              
                <!--
Some YouTube video embedding is allowed on specific domains only*, and codepen is whitelisted!
Just embed this Codepen URL instead of YouTube embed URL*:
https://cdpn.io/pen/debug/oNPzxKo?v=VIDEO_ID

* For example, https://www.youtube.com/watch?v=NAo38Q9c4xA can be only embedded in .com and .io domains (or maybe more, but not in .tw), besides those, it shows "Watch on YouTube" link in the iframe only.
* Support native YouTube embed parameters like autoplay, mute: https://developers.google.com/youtube/player_parameters

Example embed code:
```
<iframe src="https://cdpn.io/pen/debug/oNPzxKo?v=dYwto5oULSk" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" allowfullscreen="allowfullscreen"><a href="https://www.youtube.com/watch?v=dYwto5oULSk target="_blank" rel="noopener">https://www.youtube.com/watch?v=dYwto5oULSk</a></iframe>
```
-->
<iframe src="https://www.youtube.com/embed/BAMiakI5_sc?si=L7_wxz6TLWqyrjRE" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" allowfullscreen="allowfullscreen"></iframe>
              
            
!

CSS

              
                html {
  overflow: hidden;
}
iframe {
  width: 100vw;
  height: 100vh;
}
              
            
!

JS

              
                (() => {
  const url = new URL(window.location)
  const vid = url.searchParams.get('v') ?? 'BAMiakI5_sc?si=L7_wxz6TLWqyrjRE'
  url.searchParams.delete('v')
  const embedUrl = new URL(`https://www.youtube.com/embed/${vid}?${url.searchParams.toString()}`)
  document.querySelector('iframe').src = embedUrl.href
})()
              
            
!
999px

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