I have come this far:
http://w3webseiten.eu/
What is missing is the menu getting to (display:none), the moment the width gets medium or small.
[edit]
Of cause, mediaqueries . . .
Now I will make the menu get over the content, then I am at the same point that the examples had
I used before where the menu is positioned fixed.
Putting the problem in words is a part of the solution!
regards.