Hi.,
1). Yes, you can change the Menu-bar BG using the backend option as aforesaid.
Appearance->Woo Shop Options->Colors->Menu tab
Also, you can change the active item style as you wanted like Jewelry demo, using or by changing the option namely, “menu-active-highlight” from the current selection easily..
If you have any difficulties with it means, please get back with your site login access (WP & FTP) immediately, and then we’ll help you get rid of it ASAP..
2) https://helenaartstudio.com/shop/ – Sorry, You cant add this filter into gallery pages. If you want, You can add this filter https://prnt.sc/sgi4bm on your gallery page.