Calendar in k2 events list and Mobile menu in k2 item view

In k2 events list (http://www.teatroscuola.cloud/home/k2-categories),
when clicking on "«" or "»" in calendar module to change month,
you get directed on new page with only the calendar and nothing else:
http://www.teatroscuola.cloud/index.php ... temid=1199

Is it possible to change that? At least to have a link that opens a modal popup?
Or better remaining in the same page.

The same thing happens in single item view:
www.teatroscuola.cloud/home/k2-categori ... ca-di-dory

On this page there is another problem:
Link to open mobile menu is not working. Mobile menu doesn't open when clicking on it.

Thanks for helping!

I had to unpublish calendar module. You can see the calendar issue also on your demo in event listings.