Change background image in Learner Self-Service area

Content

Hi all!

I am trying to change the background image in Learner's Self-Service area. The black one in the screen attached. I tried to change it through Page Composer, in the Style tab by inserting the URL of the image (uploaded in the Content Server). But when I enter with another user, my image does not show up.

Do you know how to change it for all users?

 

Thank you,
Giorgio