Brand colors fail minimum thresholds for accessible color contrast (namely, a luminosity difference ratio of 4.5:1 or greater). This is a Web Content Accessibility Guidelines (WCAG) 2.2 standard for text that is smaller than 18pt (see Success Criterion 1.4.3 Contrast (Minimum)).

So, Tithe.ly brand text link color should use a darker green text on white (with underlining) and CTA buttons colors with white text on darker green background.

RHO