Decrease header

Hi,

If someone would like to help, it would make me glad! 🙂

I’m stuck trying to decrease the header in whitch the logo and menu is in.
I can change the logo and fill out with white area to change some, but the result is’t that good. Can I put a css code in the css-code-box that determines the height os the header?

I would also like the large image to get close to the header, without the grey gap/margin between.

I’ve got the Bento-theme

Thank you!
Magdalena

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