Cascading Style Sheets, Level 2 - World Wide Web Consortium

At the lexical level, CSS style sheets consist of a sequence of tokens. The list
of tokens for CSS2 is as follows. The definitions use Lex-style regular expressions.
Octal codes refer to ISO 10646 ([ISO10646]). As in Lex, in case of multiple
matches, the longest match determines the token.
Token
Definition
IDENT
ATKEYWORD
STRING
HASH
NUMBER
PERCENTAGE
DIMENSION
URI
UNICODE-RANGE
{ident}
@{ident}
{string}
#{name}
{num}
{num}%
{num}{ident}
url\({w}{string}{w}\)
|url\({w}([!#$%&*-~]|{nonascii}|{escape})*{w}\)
U\+[0-9A-F?]{1,6}(-[0-9A-F]{1,6})?
CDO
; ;
{ \{
} \}
( \(
) \)
[ \[
] \]
S
COMMENT
FUNCTION
[ \t\r\n\f]+
\/\*[^*]*\*+([^/][^*]*\*+)*\/
{ident}\(
INCLUDES ~=
DASHMATCH |=
DELIM
any other character not matched by the above rules
The macros in curly braces ({}) above are defined as follows:
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