Burger menu is transparent and overlays content (dev version)

[psobolewskiPhD]

When having the napari.org page narrow enough to trigger the top bar to change into the burger menu, clicking and opening the burger menu results in an overlay with transparency, which makes it hard to read things:

macOS 13.1 Safari 16.2 Chrome 109.0.5414.87

BTW, any chance the menu items could be right-justified, so they'd pop out under the burger menu? less mousing that way.

[psobolewskiPhD]

This is fixed by #134 Burger is on the left and the menu slides out from the left so it's less mousing and everything is readable