At-rules control how CSS behaves.
Statement at-rules end with a semicolon, while block at-rules end with curly braces.
Some at-rules use at-rule functions and descriptors.
Certain at-rules, such as @container, @layer, @media, @scope, @starting-style, and @supports, can be nested.
Statement At-Rules #
@import imports styles from other stylesheets.
@import must be at the top except @charset and @layer.
The @import at-rule with the layer keyword creates an anonymous layer.
The @import at-rule with the layer() function creates a named or anonymous layer.
@layer declares a cascade layer.
@layer creates one or more named layers as a statement at-rule.
@layer creates a named or anonymous layer as a block at-rule.