From the Website Width option in your Theme-Options you can choose Full-Width or Boxed Style. It is important to remember that – If you choose Boxed Style, do not forget to edit the Rows of your pages. Click on the edit icon of the Rows and select Default from the drop-down options of Row stretch. Otherwise you may see the pages sections are not properly styled into the Box.
For Full-Width page you need to choose Stretch row and content (no paddings) from the drop-down options of Row stretch.