Hello Ryan James !

It can be changed via editing the settings of CSS classes included to the current layout. For example, the columns from the layout with right bar depends on .bx-layout-bar-right-content class (left column with 66% by default) and .bx-layout-bar-right-bar (right with 34%). So you need to check the necessary layout with the browser developer tool and check which classes set the width of the column, then change it via your own mixes.