Transparent header?

Does anyone know if you can get a transparent header? My plan is to put background, header and logo in the order below, but the transparent png image I put in the header seems to turn into white. (while logo image works fine as transparent):

Back layer: background Image
Middle layer: Transparent header
Front layer: Logo Image with transparent background and white text.

I also have a question about the white box just above the footer. It wasn’t there before and I like to get rid of it …

Site: http://www.formgivningsfabriken.se

Thanks!