Hi Tom,
its my problem but i want create new website with GP. But i have problem with menu. I tried change background menu to trasparency. This is my site http://www.i-webhosting.cz/ . On top i have black background under nav menu. But i use .is_stuck + .sticky-spacer {display:none!important;} and now when you goes down and next to top it is great.. Navigation background is invisible and page content starts. I hope you understand.