feat(landingpage): tweak navigation design

[TobiasHeimGalindo]

Closes #995

Proposed Changes

Video.mp4

[BingeCode]

Since we're already tweaking some things about the navigation, here's two more things that could be improved (perhaps in another story):

1. Add padding and hover effect to the menu items so that it's easier to click them (see inovex.de homepage for reference)
2. Navigation items without sub menu should not have a context menu pop up. IMO inovex.de handles that elegantly by underlining those navigation items (picture 2)

[TobiasHeimGalindo]

Since we're already tweaking some things about the navigation, here's two more things that could be improved (perhaps in another story):

1. Add padding and hover effect to the menu items so that it's easier to click them (see inovex.de homepage for reference)
2. Navigation items without sub menu should not have a context menu pop up. IMO inovex.de handles that elegantly by underlining those navigation items (picture 2)

@BingeCode sounds and looks good. I will implement this in this PR

[BingeCode]

Looks nice!
I also noticed that the navbar doesn't toggle to mobile view at the correct breakpoint - it extends further than the viewport allows. Same for the rest of the landingpage, perhaps this should be tackled in a separate story