Saving CSS changes in Customizer broke styling across the whole site

Hi. This is my first time working on a Beaver Builder site. (I have used Divi a lot).

I was doing fine until I added some CSS to the Additional CSS in the Customizer. This broke styling for buttons, fonts and all sorts of other things across the entire site.

I deleted my changes but everything still broken.

Has anyone got any idea why this could have happened? And know how I can revert it without having to go in and style all of those things again?

Thanks
Gavin

Additional CSS is a WP core themes feature, nothing to do with any BB product.

What it does sound like is you are battling one or more caches.