The default project background color of WireframePro is white. However the background color can be set before project is created and it can be also changed anytime later from page's grid settings.
Note: Background color is applied common for all pages in that project and it cannot be set individually per page.
Set background color in project create dialog of dashboard
1.Set project background as transparent
2.Set project background as white
OR inside project editor after it is created.
1.Open page settings.
2.Disable transparent background
3.Choose any background color