User Preferences for Colors, the CSS3-Color Module, & the CSS3-UI Module

aloha, all!

recently, a Last Call publication request for CSS3's color module:

was posted to www-archive; the resultant thread can be found at:

the upshot of this request, is a new Last Call draft of CSS3-color, 
date-stamped 21 July 2008, which can be found at:

this reminded me of a thread on wai-xtech from december 2007

in which i queried the list for information concerning support for the 
CSS2 and CSS2.1 "User preferences for colors" -- the reply that stuck 
with me from that thread was patrick lauke's reply, noting his query to 
the www-style list inquiring why system colors have been deprecated in 
CSS3's color module:

in which patrick also referenced his "CSS System Preferences Test Page":

as for the 21 July 2008 CSS3 Color draft, section 4.5 "CSS System Colors":

is marked as "deprecated" -- at the very end of the section is a note


The CSS2 System Color values have been deprecated in favor of the CSS3 UI 
'appearance' property for specifying the complete look of user interface 
related elements

rather than providing a simple, straightforward means of applying 
user-defined system preferences and colors as was the case with CSS2
and CSS2.1

there is a cautionary note which immediately follows section 4.5


4.6 Notes on using colors

Although colors can add significant amounts of information to document 
and make them more readable, please consider the W3C Web Content 
Accessibility Guidelines [WCAG] when including color in your documents.

[link] Guideline 2. Don't rely on color alone.

obviously, the best way to respect a user's preferences and settings is
to reuse system color values and preferences that a user has set for for
his or her system

the reference in the first quote, although it cites the "CSS3 UI 
'appearance'", does not include a link to the CSS3-UI module, which has 
been in Candidate Recommendation since 11 May 2004, and which is located 

the pertinent portion of the CSS3-UI module is Section 5: "System 
Appearance"; and the CSS3-UI 'appearance' values are defined at:


CSS2 introduced the concept of system colors, which is a set of keywords 
that allows authors to specify colors in a manner that integrates them 
into the user's graphic environment. However, color is not the only 
property for which native form controls have a default. 

The properties defined and extended in this section refer to the 
<appearance> value type, which may take one of the following values which 
have been derived from the list of CSS2.1 System Colors ([CSS21], section 
18.2), the list of HTML4 form controls ([HTML401], section 17), and 
additional typical platform user interface (UI) controls (e.g. dialog 
window, icon): 

[list of properties and values snipped]

Conforming user agents must support the five generic appearance values: 
'icon', 'window', 'button', 'menu' and 'field'. If a user agent or 
platform does not support a specific user interface element (e.g. 
'dialog'), it may apply the values for the respective generic user 
interface element (e.g. 'window'). 

Note. This specification recommends that user agents allow users to 
override system appearance and font selections with their own choices or 
proportions, within the user agent. See the User Agent Accessibility 
Guidelines, specifically Ensure user control of rendering ([UAAG10], 
section 2 guideline 4). 

patrick, have your inquiries ever been answered to your satisfaction?  
the recorded "disposition of issues" in response your comment, referred
to above, logs

as the Group response, with the "resolution" being "no change"

is this something that WAI should be tracking and persuing?  if so, how 
far should the WAI go -- simply ask for a justification for the 
deprecation of CSS3-Color's section 4.5 "CSS System Colors", or for 
reinsertion of this particular section into the CSS3-Color module?

a few considerations:

1. the CSS3-UI spec has a dependency on the CSS3-Color module

2. the CSS3-UI draft has been in candidate recommendation for slightly
   over 4 years -- would it benefit accessibility for the WAI to argue 
   that since CSS3-UI remains in limbo and there are no documented 
   implementations of the CSS3-UI module

3. on the other hand, CSS3-Color, has cycled backwards from 
   "Candidate Recommendation" on 14 May 2003, to the new Last Call 
   draft issued 21 July 2008:

   the deadline for comments on the second Last Call draft for CSS3-color
   is 1 September 2008

4. in the CSS Snapshot 2007 (a.k.a. "CSS Beijing") CSS3-Color is included
   in the "Cascading Style Sheets Definition"


   3. Cascading Style Sheets Definition

   At the time this specification enters Candidate Recommendation, 
   Cascading Style Sheets (CSS) is defined by the following 
   specifications. Each specification in this list builds on and possibly 
   modifies the definitions in the previous specifications, with the base 
   formed by CSS Level 2 Revision 1. (In other words, CSS is defined as 
   CSS Level 2 Revision 1, modified by CSS Namespaces, modified by 
   Selectors Level 3, etc.) A valid CSS document is one that conforms to 
   this definition. 

   CSS Level 2 Revision 1 (including errata)

   CSS Namespaces

   Selectors Level 3

   CSS Color Level 3

which seems to indicate that, due to all available developmental and 
implementation information, the WAI SHOULD be advocating the restoration
of section 4.5 "CSS System Colors" in CSS3-Color itself, as CSS3-Color is 
earmarked by the Style activity as part of the "CSS definition", whereas 
there is absolutely no mention of CSS3-UI in the CSS Snapshot document

You cannot depend on your eyes when your imagination is out of
focus.                                           -- Mark Twain
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Received on Monday, 21 July 2008 17:45:11 UTC