How to make double navbar with buefy?

Question

css

I am an absolute noob at the frontend. I want to make double navbar like

here

and so that on the mobile version all this is folded into one hamburger menu. And all this must be done using Buefy. I sit for an hour and have not the slightest idea. Help.

Answer 1

I did not understand about the "double"
And what did the example not fit in the documentation? https://buefy.org/documentation/navbar