Syntax Used in CSS Property Definitions

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<Foo>

Value of type Foo. Common types are discussed on the Units page.

Foo

A keyword that must appear literally (though without case sensitivity). Commas and slashes must also appear literally.

A B C

A must occur, then B, then C, in that order.

A | B

A or B must occur.

A || B

A or B or both must occur, in any order.

[ Foo ]

Brackets are used to group items together.

Foo*

Foo is repeated zero or more times.

Foo+

Foo is repeated one or more times.

Foo?

Foo is optional.

Foo{A,B}

Foo must occur at least A times and at most B times.