Mobile view enlarging

Hi there,
is there a way to enlarge the editing field of the mobile view? I have a very broad header (although on mobile it does not show all elements) and I cannot well edit other presets and contains in the mobile view.

See here

Is there a way to increase the “Sichtfeld” when I edit the mobile website? I tried with zoom, but then it just generally zooms in or out.

Thanks a lot and regards,