How to change font of a menu?

Hello.

I’m using the “Initio” theme and have encountered a problem with font changing.
I’ve changed the font on all of the website by pluggin in the selected Google font (PT Sans) to functions.php, and then adding it to style.css (font-family).

However, the font hasn’t changed in the menu of a website, and I don’t know how to deal with that problem. I’ve tried many things, nothing works.

I would be grateful for and advice.