How Do I Fix The Mobile Version of My Website?

[NxtGenHumans]

Hello, 

My mobile version does not show the header picture properly. When I click to edit the mobile version of my site it says I'm not able to. 

Do I need to upgrade something? Pick a different layout? 

I see other websites have a version of their website for the PC and a version of the website for mobile.  My mobile looks terrible. 

Website name is Ericpellini.com 

[Bernadette3]

The mobile site is displaying properly, but I'm not sure if you have updated or changed the theme since posting. This theme you are currently using is the only theme that has a split vertical header on desktop, but will not show this way on mobile due to the screensize.