Why isn't my media query distributing horizontally?

I’m starting with CSS grid for a mobile-first approach, then using a media query with grid to change the layout on larger screens. Yet on a large screen I still have a single column rather than the six columns I thought would be the result.

Looks like you have funky double quotes wrapping around class boxes ”boxes”.

It needs to be "boxes".

I would remove funky double quotes and re-type proper double quotes.

Well don’t I feel like a fool. Thank you.