OliveWP theme allows you to change the width of the content area. To change the value just slide the pointer to the left or right or enter the fixed value in the box.

Location: Appearance >> Customize >> General Settings >> Container Width

Container Width

Set the width of the container.

Content Width

Set the width of the content which is covered on the screen.

Sidebar Width

Set the width of the sidebar which is covered on the screen.

For additional features: Width of the Content Area (Pro)