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Re: An Accessible method of hiding HTML content


From: Derek Featherstone
Date: Jun 5, 2004 12:52PM

paulb wrote:
> Some users with low vision change the background colors without
> overriding the entire style sheet. If they override the entire
> style sheet, then there is no problem, because the text will
> display properly, in the correct location. However, if they
> turn off only the background styles, then the text remains hidden
> and the background image also disappears. This creates
> an instance of a missing heading.

This point is really at the crux of the issue. We regularly teach developers
that when they are building their CSS rules that they ensure they declare
backgrounds (either images, or colours) with an appropriate foreground so
that if images are off, or stylesheets are off, or in some other situation,
there is appropriate contrast between foreground and background. The W3C's
CSS Validator even flags this issue as a warning.

My questions then are:

1. What mechanisms are these low vision users using to override the styles?
Browser settings? User Style Sheets? Other?
2. Where are they learning how to do so? On their own? From tutors? From
online resources?
3. Can we realistically expect the users or those teaching them to override
styles to do so in a way to ensure that both foreground and background are
overridden so there is no conflict as you suggest?

I'd like to think that if someone has figured out on their own to override a
background colour, then it is reasonable that they would also have the
ability to override the foreground colour. I'd also like to think that
anyone producing training materials would be able to express the importance
of overriding both foreground and background settings.

Your thoughts?

Best regards,
Derek Featherstone <EMAIL REMOVED>
phone: 613.599.9784; toll-free: 1.866.932.4878 (North America)
Web Accessibility Specialist / Co-founder of WATS.ca
Web Accessibility Testing and Services http://www.wats.ca