Something like this is easily accomplished with Weaver Xtreme. All the listed settings are found on the Main Options : Wrapping area, or on the Spacing, Widths, and Alignment menu on the Customizer.
1. Set your theme width to as wide as you want the maximum width. If you really want the theme to be full width even on very wide screens, use something like 9999 px. 2. Set the width of the container to some % – such as 80 or 70, and center align it.
If you want the content area to have a max width of 1050, you need the Weaver Xtreme Plus plugin. There you would still center the container area, but set the Max Width to 1050px.