CSS selectors define the elements to which a set of CSS rules apply. There are no selectors or combinators to select parent items, siblings of parents, or children of parent siblings.

These functions may be used wherever an <image> is valid as the value for a property.

Functions that specify different color representations. These may be used anywhere a <color> is valid.

The <filter-function> CSS data type represents a graphical effect that can change the appearance of an input image. It is used in the filter and backdrop-filter properties.

The math functions allow CSS numeric values to be written as mathematical expressions.

CSS Transform functions with an example of some function

CSS functional notation is a type of CSS value that can represent more complex data types or invoke special data processing or calculations.

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