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HTML

CSS

CSS Base

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JavaScript

Babel includes JSX processing.

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HTML

              
                Trying out [conditional @import rules](https://drafts.csswg.org/css-cascade/#conditional-import) from the spec.

Every single one of these URLs load (check the network panel) but the styles don't get applied. Try tweaking one of the queries and you'll see them applied. You can change if they get applied, but not if they load 
              
            
!

CSS

              
                /* Loads the URL, DOES NOT apply the styles */
@import url("data:text/css,body{background:red}") (min-width: 100000000px);

/* Loads the URL, DOES apply the styles */
@import url("data:text/css,body{background:lightgreen}") (min-width: 1px);

/* Loads the URL, DOES NOT apply the styles */
@import url("data:text/css,body{background:red}") supports(foo: bar);

/* Loads the URL, DOES NOT apply the styles, BUT IT SHOULD */
@import url("data:text/css,body{background:blue}") supports(display: block);

              
            
!

JS

              
                
              
            
!
999px

Console