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Specify a list of allowed name and unit pairs within media features.

@media (width: 50em) {}
/** ↑ ↑
* This media feature name and these units */


object: { "name": ["array", "of", "units"]|"unit" }

If a feature name is surrounded with "/" (e.g. "/height/"), it is interpreted as a regular expression. This allows, for example, easy targeting of shorthands: /height/ will match height, min-height, max-height, etc.


"width": "em",
"/height/": ["em", "rem"]

The following patterns are considered problems:

@media (width: 50rem) {}
@media (height: 1000px) {}
@media (min-height: 1000px) {}
@media (height <= 1000px) {}

The following patterns are not considered problems:

@media (width: 50em) {}
@media (width <= 50em) {}
@media (height: 50em) {}
@media (min-height: 50rem) {}