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Re: CSS Transparent Background and 1.4.3?

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From: Jim Homme
Date: Jan 24, 2017 10:17AM

Hi,
From the below, I'm translating that the test is inclusive, and that to ensure a valid test, we should advise the developer to code an explicit background color. Is that accurate?

Thanks.

Jim


=========Jim Homme,
Team Lead and Accessibility Consultant,
Bender HighTest Accessibility Team
Bender Consulting Services, Inc.,
412-787-8567,
<EMAIL REMOVED>
http://www.benderconsult.com/our%20services/hightest-accessible-technology-solutions
E+R=O

-----Original Message-----
From: WebAIM-Forum [mailto: <EMAIL REMOVED> ] On Behalf Of Patrick H. Lauke
Sent: Monday, January 23, 2017 7:19 PM
To: <EMAIL REMOVED>
Subject: Re: [WebAIM] CSS Transparent Background and 1.4.3?

On 23/01/2017 18:28, Jim Homme wrote:
> Hi, According to what I just read, transparent is the default if a CSS
> background color isn't coded by the developer. Since I'm totally
> blind,, how does that affect testing for 1.4.3, contrast? For
> instance, are the results different for black text on a white
> background, specifically coded, than they are if the developer just
> specifies black text and allows the default to take over?

Assuming you mean a developer doesn't set explicit background color anywhere, including the body/html elements:

- browsers used to default to a medium/light grey colour as the default; however, most (all?) browsers these days default to a white default for the body/html

- users *may* have specified that their browser should use specific custom default colours. For this reason, not specifying at least an explicit colour for the body/html elements in addition to a foreground colour would lead to the explicitly defined foreground colour being displayed over any kind of colour - making this impossible to test for conclusively since it will depend on the user's settings (unless your evaluation explicitly mentions that the result is only valid for default browser values).

P
--
Patrick H. Lauke

www.splintered.co.uk | https://github.com/patrickhlauke http://flickr.com/photos/redux/ | http://redux.deviantart.com
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