Circumference offers you three page widths:
- Full Width
- Boxed Medium
- Boxed Small
Here is a screenshot of each size, where as the page gets smaller in width, more of the background is seen. Plus, on the boxed views, your page has an outer glow:
Make Your Selection
- Go to Appearance >> Customize >> Basic Settings
- Select your page width
- Click Save and Publish
Screencast Tutorial