Step 1. In your shop administration, go to 'website' >> 'Design manager'
Step 2. Click 'Custom' tab and select ?Page? from the ?Section? dropdowns.
Step 3. From ?Page Background Colour? pick your own background colour
Step 4. Click "save" button and then click "ok" button
Step 5. Now go your website and refresh the page to view the new background color
For more information about how to use Design Manager to change the look of your site, you can also refer to our VPCart 9 User Guide at
https://helpnotes.vpcart.com/userguide900/#!Documents/howtousethisdesignmanagerfeatureinvpcart.htm