- From: Benjamin Hawkes-Lewis <bhawkeslewis@googlemail.com>
- Date: Sun, 27 Jul 2008 13:21:15 +0100
- To: Ingo Chao <i4chao@googlemail.com>
- CC: "www-style@w3.org" <www-style@w3.org>
Ingo Chao wrote: > Are vendor-specific extensions invalid? Or are they valid because the > format they should have is defined in the specification, so the > grammar is correct? The CSS 2.1 specification says: "The validity of a style sheet depends on the level of CSS used for the style sheet". The specification also says: "A valid CSS 2.1 style sheet must be written according to the grammar of CSS 2.1. Furthermore, it must contain only at-rules, property names, and property values defined in this specification. An illegal (invalid) at-rule, property name, or property value is one that is not valid." http://www.w3.org/TR/CSS21/conform.html If this statement is taken to the letter, although the specification describes how to parse vendor-specific properties, the property names and values of vendor-specific extensions are not defined in the specification, so they are invalid CSS 2.1. The CSS validator correctly flags vendor-specific extensions in CSS 2.1 stylesheets as errors. They might conform to some other, hypothetical, CSS level, however. -- Benjamin Hawkes-Lewis
Received on Sunday, 27 July 2008 12:21:53 UTC