Miscellaneous Syntax Details
= Index DOT Css by Brian Wilson [bloo@blooberry.com] =

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Unicode Character Escape Mechanism
The base character set for CSS is Unicode, a set which allows for approximately 65,000 characters and extension mechanisms allowing for millions more.) Keyboards are just not capable of directly inputing all of these characters. Yet, there will likely be times when an author wishes to use a character that can not be directly input from the keyboard. A special new syntax in CSS2 allows for this.

Use of the backslash character ("\") indicates that what follows is an escape sequence for a Unicode character. The hexadecimal escape code that follows the backslash represents the desired Unicode code point. As many as six hexadecimal digits may be specified after the backslash character, but fewer may be used. Unlike in HTML, character references in CSS have a beginning delimiter, but no end delimiter other than the constraint that there will be no MORE than 6 hexadecimal digits for the reference. For character references LESS than 6 hexadecimal digits in length, appending the value with a white-space character ensures that the Unicode value reference is properly terminated. In CSS2, The first trailing white-space character following a Unicode character reference should be ignored.

    "\" [0..9a..f]{1,6} [" "]?
    (eg: "\00007btext" --> "{text")
CSS Comments
CSS1 | CSS2 | IE3 | N4 | O3.5
While Cascading Style Sheet syntax is very self-documenting, there will be times when an author will want to add explanations or comments in a style sheet. CSS syntax allows for this. A CSS comment (like in the C programming language) begins with "/*", and ends with "*/" - everything that lies between these delimiters is the comment and should be ignored by the CSS parser. Comments may not be nested and can occur anywhere between CSS syntax constructs.

The specification does not seem to be clear on how HTML/XML comment constructs ("<!-- -->") are treated in CSS syntax.
'!important' Rules
CSS1 | CSS2 | IE4 | O3.5
CSS allows both the author and the reader to specify style information for a document. An author's style sheet will usually contain rules attempting to preserve the original design intent; a user's style sheet may contain style rules that are imperative for their viewing needs (eg: possibly larger font sizes for users with poorer eyesight.)

By default, style rules in an author's style sheet will have higher precedence than an equivalent style rule in a user's style sheet. This skews the decision-making of page rendering decidedly towards the author, which can be very limiting for some users ...to the point of making content exclusionary in some cases.

CSS allows the scales to be balanced with the "!important" keyword. When this keyword is added at the end of a style declaration (eg: "h2 { color: white !important }") it is given higher precedence than an equivalent style rule that does not carry the "!important" keyword. When equivalent style rules in an author and user style sheet both carry the "!important" keyword, the user's style rule takes precedence.

Browser Peculiarities
Boring Copyright Stuff....