Hey @odog it takes a few interactions. Making this responsive in the way that this nav was built would be quite tricky though. I made a gif showing the interactions I applied to get this to function how you’d like it to on desktop devices at least. 
Basically an interaction on the “Device” button, to make the “Level 3” div display: block. And when hover out or on Dropdown close, make that “Level 3” div, display: none.
Please let me know if this solves the problem, if not, I’m happy to help further 