➕ ADD: modern-css-reset

[colorful-tones]

Addresses #61

[audrasjb]

+1 for this 👍

[MaggieCabrera]

I'm not sure we need all of this on this particular theme. While a reset file is a good thing to have in general on a site, on a block theme there's a lot of this stuff that is already covered by the editor and the block themselves. I'd suggest we add these rules only when we need them, not by default just because.

[kjellr]

Closing as per notes in #61 (comment).