CSS Rules

Everything a stylesheet can carry besides declarations: the at-rules that decide when a block of rules applies, and the syntax that decides how rules are written and how they rank against each other.

• @media applies a block when the screen, the player or the device matches
• @container applies a block when an ancestor’s size or style matches
• @supports applies a block only where ReactUnity has the property or value it names
• @layer orders groups of rules independently of how specific their selectors are
• @scope limits a block to one subtree
• Nesting puts a rule inside another instead of repeating its selector
• @property registers a custom property, so var() reading it has a value everywhere