WCAG 1.4.11: Non-text Contrast
WCAG 1.4.11 Non-text Contrast is a level AA success criterion from WCAG 2.1. User-interface parts and meaningful graphics need at least 3:1 against adjacent colours. This covers input borders, icons and chart lines.
People who can read the text may still miss a faint input box or a pale icon.
How to test
Measure the input border and the icon against the background. The ratio should be at least 3:1.
How to fix
Darken borders and icon strokes. Do not rely on a 1 pixel #ddd box.
Example that fails
A newsletter field has a #e6e6e6 border on white.
Example that passes the check
The field border is #1a1714.
Shopify
In the theme CSS, darken input borders and header icon strokes.
WooCommerce
Update quantity-button and input border colours in the theme.
WordPress
Set form border colours in the block or theme CSS to a dark neutral.
Wix
Select the input and set a darker border in the design panel.