Background colour, footer edit and menu language (in mobile version)

Hello, Please help me fix the following issues: 1. I want to change the background colour of the main body and footer for white. I tried to change the settings of the theme, but it changed only in some parts, while in other parts it remained grey. 2. I've got the MENU in the mobile version. Question A: How can I change the language of it? Question B: How can I remove this MENU from the mobile version? website: redact.agency Thank you a lot!