I've never done it but I know its possible. You need to look into adding styling to the repcontainer class and its repitem elements. When a repeating section is rendered on the character sheet, roll20 creates a repcontainer elements, and then puts every row inside a repitem inside that repcontainer. So you can change the ordering by using grid, flex, or whatever (probably flex, or grid if you want a specific number of columns), on the repcontainer, to control how the repitem elements flow. To target a repeating section named repeating_items you'd use .repcontainer[data-groupname=repeating_items] and if you want to style the "rows" inside it .repcontainer[data-groupname=repeating_items] .repitem