All websites, apps, and other digital products and services must meet the W3C Web Content Accessibility Guidelines (WCAG) 2.1 at a conformance level of AA. This satisfies the legal requirements we must comply with under the Equality Act 2010 and in countries where there is legislation on accessibility. When using buttons with images or backgrounds, make sure that colors are accessible. They must pass the AA contrast check with a ratio greater than 3.1:1.
You can check your colors using the plugin Stark - Contrast checker.
Understanding accessibility means we can build websites that work for everyone, whatever their access needs. These simple do's and don'ts explain how you can make your websites accessible for different access needs.
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Describe images and provide transcripts for video
Follow a linear logical layout
Structure content using HTML5
Build for keyboard use only
Write descriptive links and headings
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Use images and diagrams to support text
Align text to the left and keep Keep a consistent layout
Consider producing materials in other formats (for example audio or video)
Keep content short, clear and simple
Let users change the contrast between background and text
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