Customize frames in Pro Gallery

Thanks Noah! That works for me perfectly!

It’s just that the frame is set to fit the media’s proportion (i.e. if the image is rectangle, the frame size cannot be customized to be square). I don’t mind this at all. I just want to ask if there’s a way to customize the frame to the proportion we want (for example, in Layouters or similar feature, I could set the frames to take up X% of the row).