For example: in Western cultures ... To check if you’re using the right amount of contrast, there is a list of color-contrast checking tools in the color section of the Web Accessibility: Resources ...

There are many studies on the impact of specific colors in marketing, but you need to carefully match your message with the color. There is no specific color or shade that is best for all marketing.

He then trained it on some hand-picked examples, with the aim of making palettes with decent color contrast and a solid theme, while avoiding random-looking ones with poor contrast.