Open your campus color theme
Go to Old → Core → Campus and use the campus row’s Change Theme button. The Select Branding Color Theme page keeps its existing access permissions.
Choose your layout
Classic opens first unless you save another default. Use Try the new layout or View old layout to switch. A layout in the page address takes priority for that visit. If saving a default fails, your previous choice remains; try saving again. Switching keeps the same campus, draft colors and preview.
Use your existing color controls
Primary Color, Secondary Color, Accent Color and Neutral Color keep their original pickers and text entries. Save Theme or Update Theme keeps its existing behavior. Back and Cancel return to Campus. Switching views does not save a theme. Existing loading and pending behavior remain unchanged; the layout adds no Retry or new save action.