Hey Paul, are you saying that when there are two cards on top and one on the bottom, you want the card in the bottom row centered beneath the two in the top row? Just want to make sure I understand first.
You should be able to solve this by conditionally setting the number of columns when the width of the RG hits the lower breakpoint.
Can’t recall off the top of my head whether you can set the min width of column the same way (if you aren’t using a fixed number), but if you only ever have 3 columns it shouldn’t be an issue.
…then yeah. Assuming the RG is set to horizontally wrapped, just enable the Stretch columns to fill horizontal space option. Then make sure to center the card within the RG cell. (You’ll want to set a max width for the card.)
As you can see, the space between cards in each row will vary depending on the number of items in that row; but they will be evenly distributed and thus “centered”. Not sure if it’s exactly what you want, but it’s easy peasy hot and cheesy.
Thanks for your help. I did know about this option which I should have specified in my initial post. The thing I don’t love about this option is the space this creates between cells in the RG: