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Re: CSS Transparent Background and 1.4.3?

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From: Patrick H. Lauke
Date: Jan 23, 2017 5:19PM

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

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