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Re: Using high contrast styles in a site


From: glen walker
Date: Sep 12, 2019 9:58AM

Technically, you are allowed to have a low contrast page by default as long
as there's a widget on the page to switch to minimally passing contrast
colors as long as the widget itself has sufficient contrast by default.
See the "sufficient technique" G174 -

However, even though that is allowed, I would not encourage it. If your
default page passes all contrast minimums except for a few spots on the
page, then maybe having a widget might be ok, but strive to have as much of
the page satisfy the contrast as possible.

Your specific question talked about "high contrast". This might be a
terminology thing but "high contrast" is typically a AAA requirement of
having a minimal contrast ratio of 7:1. The AA requirement is to have a
contrast of 4.5:1. But I'm thinking you were using the term "high
contrast" to just mean a larger contrast than the default page.

Having a true "high contrast" (7:1) feature is a great thing to have and
goes beyond what is required by AA. For those that are curious, an example
of a high contrast feature can be found on the State of California website,
https://www.ca.gov/. There's a "settings" menu near the top of the page
and when you expand it, there's a "high contrast" option that uses mostly
yellow text on a black background (although embedded social media content
doesn't seem to be affected).

On Thu, Sep 12, 2019 at 9:09 AM Tom Livingston < <EMAIL REMOVED> > wrote:

> Hello list,
> A coworker found an example on a website where a user could switch the
> site to use a high contrast mode. Does having a high contrast mode
> on a web site allow for the creation of content that initially doesn't pass
> color contrast tests?
> For example, if a brand color doesn't pass contrast tests, could it
> still be used as is in the 'normal' version of the site but then
> altered to pass in a high contrast mode (via css). Is this treatment
> acceptable from an accessibility stand point?
> I am looking for factual information to be able to use against this
> type of thing as it doesn't feel right to me personally, but if this
> type of thing is acceptable then I need to be able to tell designers I
> work with that they need to always plan for a high contrast mode.
> Any help would be appreciated.
> --
> Tom Livingston | Senior Front End Developer
> #663399
> > > > >