The WebPlatform project has been discontinued when the Stewards partnership agreement ended in September 2015. This site has been frozen, and the assets we have created will remain.
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A media query consists of a media type and at least one expression that limits the style sheets' scope by using media features, such as width, height, and color. Added in CSS3, media queries let the presentation of content be tailored to a specific range of output devices without having to change the content itself.