You can edit the background to your article/component area via the General -> Modules/Component Styling tab of your template setting (Extenisons -> Templates -> [YourTemplateStyle). Field name titled Article Background Color.
You can edit the background to the modules via the same template settings tab. To edit the background to individual module positions you can use the Module Style Overrides tab.
I have to give a lot of kudos to the developers of Renita. I have used a lot of Templates (free and purchased), and this one is at the top of my list for having everything I need: very user friendly, extremely flexible on allowing you to design, and change things like colors, etc. and the built in photo slide features are amazingly powerful and easy to use