Changing height of sticky border (closer to logo)

Hi there,

I want to change the height of the sticky border.
Now, that’s not too hard since it’s clear in the Theme Options.

But I want to move it closer to the logo;
see the image here: https://imgur.com/THuYVcg

It should have the exact height, so it seems the header just is an extension of the logo.
When I shrink the size of the header, the logo shrinks with it.

Thank you!
L