Change background color

Hello,
I’ve just create a link with the plugin to my wpordpress site (https://bocciobistrot.com).
I’m using “Maywood” theme with all black background.
When I generate a build the app (i’m testing it only on Andoid systems) has a white background. How can I change the background color to make the same look and feel of the wordpress site?
Despite I’ve changed theme colors on Look $ Feel section of the plugin the background color remain white. I’ve tested “Card view” and “News” theme, the only ones exists.
Thanks in advance
Marco