Color contrast is a key part in designing ADA-compliant web experiences.
The rules for color contrast come from WCAG 2.1 (Web Content Accessibility Guidelines) which define how to make web content more accessible to people with disabilities.
WCAG 2.1 lists the following for color contrast guidelines:
The visual presentation of text and images of text has a contrast ratio of at least 4.5:1, except for the following:
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