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Amend "contrast ratio" term #4400

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Amend "contrast ratio" term #4400

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5b9d281
Remove smoothing/anti-aliasing note
patrickhlauke May 17, 2025
c80725d
Remove two notes
patrickhlauke May 17, 2025
1bdcf62
Move note about border for text into understanding
patrickhlauke May 17, 2025
c071e54
Tweak 1.4.11 note about anti-aliasing
patrickhlauke May 17, 2025
0b7c816
Move note about border for text into enhanced understanding
patrickhlauke May 17, 2025
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23 changes: 0 additions & 23 deletions guidelines/terms/20/contrast-ratio.html
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Expand Up @@ -15,29 +15,6 @@

<p class="note">Contrast ratios can range from 1 to 21 (commonly written 1:1 to 21:1).</p>

<p class="note">Because authors do not have control over user settings as to how text is rendered
(for example font smoothing or anti-aliasing), the contrast ratio for text can be
evaluated with anti-aliasing turned off.
</p>

<p class="note">For the purpose of Success Criteria 1.4.3 and 1.4.6, contrast is measured with respect
to the specified background over which the text is rendered in normal usage. If no
background color is specified, then white is assumed.
</p>

<p class="note">Background color is the specified color of content over which the text is to be rendered
in normal usage. It is a failure if no background color is specified when the text
color is specified, because the user's default background color is unknown and cannot
be evaluated for sufficient contrast. For the same reason, it is a failure if no text
color is specified when a background color is specified.
</p>

<p class="note">When there is a border around the letter, the border can add contrast and would be
used in calculating the contrast between the letter and its background. A narrow border
around the letter would be used as the letter. A wide border around the letter that
fills in the inner details of the letters acts as a halo and would be considered background.
</p>

<p class="note">WCAG conformance should be evaluated for color pairs specified in the content that
an author would expect to appear adjacent in typical presentation. Authors need not
consider unusual presentations, such as color changes made by the user agent, except
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