3 Column Preview Card using HTML, CSS and CSS Grid

This was my first attempt using CSS Grid. I quite like how easy it is to change the layout using media queries.

I do have two questions though:

1. Regarding media queries, is it better practice to put them at the end of your CSS document, or under the section that it affects, like I've done with this challenge?

2. In this challenge, I've disguised an anchor tag as a button. Is it better practice to rather use <button></button> and nest the a tag in that? I find the styling to be more difficult doing it that way though, but I worry later down the line I won't be able to "submit" data.

Thanks for the help!