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Re: Color Contrast/G148

From: Christophe Strobbe <christophe.strobbe@esat.kuleuven.be>
Date: Mon, 10 Aug 2009 10:51:55 +0200
Message-Id: <>
To: w3c-wai-ig@w3.org
Hi William,

At 21:39 7/08/2009, W Reagan wrote:
>I only have two items that specify color.. 1) Headings and 2) a 
>horizontal line.
>How can I keep my existing colors for my headings and horizontal 
>line, and still pass G189.

There is no conflict between G189 and colours for headings or horizontal lines.
In fact, if your colours pass SC1.4.3 or SC1.4.6, why would you need 
technique G189? Does your site fail other success criteria at the 
level you want to reach?

>For colors of white backgroud white black text, my style sheet will 
>not parse unless I specify backgroud-color: #FFF.
>Therefore, it contradicts Parsing 4.1.1.

SC4.1.1 does not enforce a white background in CSS; you can use any 
colour that provides sufficient contrast at the level you want to claim.

>I need to pass Parsing and Color Contrast.
>I am using G189 because there is a reference to Consistent ID, which 
>I also need to pass.
>Can I kill four birds with one stone? (1) Color, (2) Parsing, (3), 
>Consistent ID, and (4) G189?

It is still not clear why you think you need G189.

Best regards,


>As of now, color is set at level AA, and Parsing passes.
>What work needs to be done.
>FYI: I will not document my site or give any attachment.
>--- On Fri, 8/7/09, Christophe Strobbe 
><christophe.strobbe@esat.kuleuven.be> wrote:
>From: Christophe Strobbe <christophe.strobbe@esat.kuleuven.be>
>Subject: Re: Color Contrast/G148
>To: w3c-wai-ig@w3.org
>Date: Friday, August 7, 2009, 8:50 AM
>Hi William,
>At 10:03 7/08/2009, W Reagan wrote:
> > Is the intent of this G148 
> <<http://www.w3.org/TR/2008/NOTE-WCAG20-TECHS-20081211/G148>http://www.w3.org/TR/2008/NOTE-WCAG20-TECHS-20081211/G148>http://www.w3.org/TR/2008/NOTE-WCAG20-TECHS-20081211/G148 
> used to evaluate the paragraph, link color, heading color, style sheet, or all?
>Using this technique, a developer does not specify any foreground or 
>background colours. The consequence of this is that the user sees 
>all the content in the default colours configured on his/her system 
>(browser settings and possibly high-contrast colour scheme on his OS 
>desktop). So you basically defer the responsibility for sufficient 
>contrast to the user (or whoever configured their computer).
>As soon as you define a foreground or background colour, you are not 
>using technique G148, and you need to look at 
>and test each foreground-background combination (including every 
>link state - hover, focus, active, ... - and, if applicable, 
>different states in form controls (for example, some developers 
>change the background colour of a control on focus)).
>Best regards,
>-- Christophe Strobbe
>K.U..Leuven - Dept. of Electrical Engineering - SCD
>Research Group on Document Architectures
>Kasteelpark Arenberg 10 bus 2442
>B-3001 Leuven-Heverlee
>tel: +32 16 32 85 51
>"Better products and services through end-user empowerment" 
>Please don't invite me to LinkedIn, Facebook, Quechup or other 
>"social networks". You may have agreed to their "privacy policy", 
>but I haven't.

Christophe Strobbe
K.U.Leuven - Dept. of Electrical Engineering - SCD
Research Group on Document Architectures
Kasteelpark Arenberg 10 bus 2442
B-3001 Leuven-Heverlee
tel: +32 16 32 85 51
"Better products and services through end-user empowerment" 
Please don't invite me to LinkedIn, Facebook, Quechup or other 
"social networks". You may have agreed to their "privacy policy", but 
I haven't.
Received on Monday, 10 August 2009 08:52:43 UTC

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