Space Between Buttons in CSS

What is a good way to put space between buttons when the parameters are defined in CSS? Here’s my current work:

I tried copying suggested code from a different site which ended up stacking my buttons vertically. Best I could do after that was a lot of CTRL-Z and coming here.

Also, could someone take a look at line 23 in the same pic, and tell me if anything there is irrelevant or in error? What I want is a thicker border around the buttons, and I’d like the border to be a dark blue, not black.

Bonk say thank you.

Have you tried using margins?

The border rule takes three arguments: color, width, style (in any order).
eg border: red 2px solid

Have you tried using margins?

I wouldn’t know how to go about that, as I have been using CSS only for a couple of days.

Edit: Just found out how! Thank you for the suggestion!

I would say margins and paddings are a good thing to try for spacing. Also flexbox could work, depending on what you mean with spacing.