Pen Settings

HTML

CSS

CSS Base

Vendor Prefixing

Add External Stylesheets/Pens

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JavaScript

Babel is required to process package imports. If you need a different preprocessor remove all packages first.

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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Behavior

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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

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HTML

              
                <!-- pri4 example using picturefill -->
<div id="image">
 <img sizes="(min-width: 640px) 50vw, 100vw"
        srcset="https://responsiveimag.es/images/Apples-200.jpg 200w,
                    https://responsiveimag.es/images/Apples-400.jpg 400w,
                    https://responsiveimag.es/images/Apples-600.jpg 600w,
                    https://responsiveimag.es/images/Apples-800.jpg 800w,
                    https://responsiveimag.es/images/Apples-1200.jpg 1200w"
        src="https://responsiveimag.es/images/Apples-fallback.jpg" alt="text" />
</div>
<div id="text">
  <p>Within the fluid context of responsive websites, the restrictive nature of the < img > element, and lack of CSS controls for foreground images, has not been the elephant in the room. It's just been the elephant that we couldn't agree what to do with…</p>
</div>

              
            
!

CSS

              
                @media (min-width: 640px) {
  #image {
    float: left;
    width: 50%;
  }
  #text {
    float: right;
    width: 50%;
  }
}

body {
  margin-left: 0;
}

img {
  width: 100%;
}
              
            
!

JS

              
                		// Picture element HTML5 shiv
		document.createElement( "picture" );
              
            
!
999px

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