Fullscreen Navigation & Filter

I've been working on a Full Screen Filter that serves as the main Navigation for an event platform.
User can browse through topics and countries. We use a technique called faceting for that. This makes it super efficient to update the count of events for certain topics or countries. This makes it possible for user to get a great overview of how many events of certain categories take place in certain countries.

I've designed and implemented and implemented the whole thing except for the logic of the faceting.

You can check it out here https://events.b2match.com
Feedback is highly appreciated!