I have also asked this question in the development-section.

I have installed the Krakatau-Lite theme. By default, it has a header with a logo, nav-menu and a sidebar (see image). I would like to add another nav-menu which is styled exactly the same as the original menu.

So basically I want to go from 2 containers to three containers. Any thoughts?
(https://www.willemvanopstal.nl)