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CSS Base

Vendor Prefixing

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Any URL's 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 it's URL and the proper URL extention.

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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.

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Add Packages

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Editor Settings

Code Indentation

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Visit your global Editor Settings.


                or more <h1>This headline is sized at 6vw. It will be 22px on mobile devices, 53px on tablets, and 100px or more on desktops.</h1>

<p>This paragraph is sized at 4vw. It will be 15px on mobile devices, 30px on tablets, and 58px and larger for desktop screens.</p>

<p>Changing the base font size in your browser will have no effect. And zooming in or out may not change the font size as much as you might imagine.</p>


                body {
  font-family: Arial, sans-serif;

h1 {
  font-size: 4.75rem; // 7vw

p {
  font-size: 4vw;