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CSS @when / @else conditional rules

A new syntax and condition system has been added that allows easy creation of advanced, media-conditioned stylesheets. The syntax also allows for easier creation of mutually exclusive portions of CSS such as making a set of media queries be written as a single @else if block

Last updated on : 2026-02-09

Browser Versions

IE

Edge

Firefox

Chrome

Safari

Opera

5.5 - 11

12 - 144

2 - 150

4 - 147

3.2 - 26.3

9.5 - 125

Fully Supported

Partially

No Support

Browser Compatibility

CSS @when / @else conditional rules on IE is not supported on any IE versions.

CSS @when / @else conditional rules on Edge is not supported on any Edge versions.

CSS @when / @else conditional rules on Firefox is not supported on any Firefox versions.

CSS @when / @else conditional rules on Chrome is not supported on any Chrome versions.

CSS @when / @else conditional rules on Safari is not supported on any Safari versions.

CSS @when / @else conditional rules on Opera is not supported on any Opera versions.

CSS @when / @else conditional rules on Safari on iOS is not supported on any Safari on iOS versions.

CSS @when / @else conditional rules on Android Browser is not supported on any Android Browser versions.

CSS @when / @else conditional rules on Opera Mobile is not supported on any Opera Mobile versions.

CSS @when / @else conditional rules on Chrome for Android is not supported on any Chrome for Android versions.

CSS @when / @else conditional rules on Firefox for Android is not supported on any Firefox for Android versions.

CSS @when / @else conditional rules on Samsung Internet is not supported on any Samsung Internet versions.

Browser Support for CSS @when / @else conditional rules

CSS @when / @else conditional rules on Chrome

CSS @when / @else conditional rules on Safari

CSS @when / @else conditional rules on Firefox

CSS @when / @else conditional rules on Internet Explorer

CSS @when / @else conditional rules on Opera

CSS @when / @else conditional rules on Edge

References

Data sourced from

0

Low

Overall Browser Compatibility Score

Note:CSS @when / @else conditional rules shows a browser compatibility score of 0. This is a collective score out of 100 to represent browser support of a web technology. The higher this score is, the greater is the browser compatibility. The browser compatibility score is not a 100% reflection for every browser and the web technology support. However, it does give you an estimate on how much you should rely on a particular web technology in terms of browser compatibility.

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