Adding Support for a Feature Query

Feature queries can be used to test if a browser can understand a CSS feature or style. With the @supports rule, the browser is asked (queried) whether or not a specific CSS property is supported. Then, if the answer is positive, the browser is instructed to apply a series of style rules.

You can create a feature query using the Choose a new support query dropdown. We have some examples prepopulated for you, like Display Grid, Display Flex, and a Blend Mode Darken. But you can also create your own using the Custom Support Query. A Feature Query is a combination of a Property (like “display” or “font-family”) and a Value (like “grid”, “flex” or “Arial”).