reduce height of dropdown menu & let it overlap instead of pushing whole website down (mobile view)

[Paul_K]

hey,

so i'm having a few issues with the dropdown menu in mobile view. 

first: it slides to far down in my opinion so that there is a big white space between the logo and the menu (image 2).

second: i would like the menu to overlap the image below it if you press the button for the menu. right now it pushes the whole website down if extended (compare image 1&2).

should look like image 3 when you click on the menu (made with photoshop) : if the shadow aint there its alright too.

URL: https://www.starlinechains.de/

hope someone can help:)

thx

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