CSS

CSS is a declarative stylesheet language used to describe the layout and presentation of HTML documents.

Why isn't this CSS doing anything?

YIJEUVTA.png

Have you ever set a width in CSS, and… nothing happens? There are a number of property & value combinations that can lead to CSS being inactive, and now Firefox will tell you why.

CSS Grid and Grid Inspector in Firefox

gridsite.width-320.png

Firefox’s Grid Inspector Tool lets you see the grid lines in the browser while you’re creating a layout or studying other examples of CSS Grid in action.

@supports on MDN

mdn_logo_only_color.png

The @supports CSS at-rule lets you specify declarations that depend on a browser's support for one or more specific CSS features. This is called a feature query.

Why isn't this CSS doing anything?

Have you ever set a width in CSS, and… nothing happens? There are a number of property & value combinations that can lead to CSS being inactive, and now Firefox will tell you why.

YIJEUVTA.png

CSS Grid and Grid Inspector in Firefox

Firefox’s Grid Inspector Tool lets you see the grid lines in the browser while you’re creating a layout or studying other examples of CSS Grid in action.

gridsite.width-320.png

@supports on MDN

The @supports CSS at-rule lets you specify declarations that depend on a browser's support for one or more specific CSS features. This is called a feature query.

mdn_logo_only_color.png

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