How can I set Absolute background on header in all pages? (not only in homepage)

Hello I'm Sandra from Spain, Can you help me? In the Free version of Izabel theme, Header had already Absolute background in homepage. As I can see in the compare section between the free and the PRO version There is one feature saying this: Absolute background on header when slider/header image is active: Enable/disable I assumed I will be able to change this in all pages not only in homepage cause there was already set that way in free version, so I purchased the PRO version, but I cant set it now. I am in Appareance ▸ Theme Options ▸ Layout Options and the option: Absolute background on header when slider/header image is active IS ON, but it only works with home page. Please help me :( I only purchase the pro version to get that feature... Thank you in advance and great theme!