You have picked a palette you like, and somewhere in review someone says the text “fails contrast”. Here is what that actually means, what the numbers are, and how to fix it without throwing the design away. What a contrast ratio is Contrast ratio is a single number describing the difference in relative luminance between two colours — roughly, how light each one is once you account for the fact that human eyes are far more sensitive to green than to blue. It runs from 1:1 (identical colours, invisible) to 21:1 (pure black on pure white). The important and counterintuitive part: it is about lightness, not hue. Two vivid, obviously different colours — a strong red and a strong green, say — can be almost identical in luminance and fail badly, while two shades of the same blue can pass comfortably. This is why “but they look completely different” is not an argument. The numbers you actually need AA, normal text — 4.5:1. The...