Four Card Feature Section using HTML, CSS and CSS Grid

This differed from the other projects I've completed, so it was an enjoyable challenge.

The only thing I'm not too sure that I did right was the border color on the top of the cards. It's hard to tell from the design image, but it looks as if the borders are inset? I tried using border-top-style: inset, but that made the colors very dark. I'm not sure why though?

Thanks for the help!