You can find the Layouts option in the theme Customizer on Appearance → Customize → General → Global Layouts.
Customize your website’s layout including full width or boxed customization along with specific sizes for content and sidebars.
Site Full Width Layout
The full-width layout is the default layout for the theme and it displays your content centered, but with a white background through-out. This layout doesn’t have any padding around the main wrapper.
Site Boxed Layout
The boxed layout has a padding around both sides of the main wrapper as well as a background applied to it so that you can apply a custom background to your body and all your content will be centered with the background flowing around it.
Container width customize the width of the container.
Sidebar Width customize the width of the Sidebar.
Content layout customize allows you to separate your website elements (content area, widgets, header, footer etc..) into separate blocks, or contain them all inside one container.