Edit column order

Hi – I can’t find an exact solution to reordering columns.

I have one color section with 1 full width column (heading), and then two columns below it at 3/5 (body copy) and 2/5 (image).

On mobile, I want to reorder these columns like so:
heading column
image column
body copy column

I tried a few solutions I found on the forums but can’t seem to get them to work. The class on the color section is as follows: column_flex_reorder-bottom

Thank you!