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Syntax Used in CSS Property Definitions

<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.