How to get your first section background image object, under the header when you auto layouted your whole web page design?

So here is the thing. I designed a website and all of the sections of the home page have auto layout and fixed width, and in my first section (Second section if you count header as a section) i added an image object in the frame then put it on absolute and sent it to back so i can put it under my header (which is transparent and has no color) to get that modern look. BUT here is the problem i wanted to auto layout the whole home page frame and then i realised because of the sorting system my first section with that background goes on top off the header and i couldnt see the header.

I’m sure this is not a problem. it is a rare case i should not auto layout my whole page i think. maybe i see the structure wrong. anyway i wanted to share with you this challenge that i had.