Using either a custom Theme or the custom CSS settings for a currently applied Theme, you can override the colour value for that title. The specific CSS selector you need is:

.block-totara-featured-links-layout>div .block-totara-featured-links-content h3 {

  color: yourNewColor;

}

If you also need to target more selectors, your best option is to use a tool like Firefox or Google Chrome devtools "Inspect Element" on individual elements, to find their selectors, and then change values from there.

Cheers,

Dave