Transpareny of main menu and borders around page titles

I want to use a quite minimalistic homepage design.

Meaning – just a big full-screen picture on the homepage.
So far, so clear..

To fulfill this purpose, I need to have the following things:

– The main menu color shall be transparent
– full screen picture shall directly start at the beginning of the page. Thus, the (transparent) main menu and the fullscreen picture shall overlap.
– Around each element in the main menu (e.g. the title of subpages), there shall be a border and the form shall have a red background.

Could you please help me with this? :)