How do I move something one one view but the other views stay the same?

I have a split column. The Navbar is placed on top of the right column. In the desktop view this is great. On the mobile view, it has the columns on top of each other which the Navbar is under the first column. On the mobile view, I want the Navbar on top, but I want it to remain unchanged on the desktop and tablet views.

Here is my site Read-Only: LINK
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You can put a nav bar on both sides, hide one on desktop/mobile, show the other on desktop/mobile.

Or, you can use flex-box instead of a grid, then you can simply click a button to swap the order of the sections for mobile.