Hi scalabria,
As you may have noticed, it’s possible to change the background of the entire section in the email editor.
What you could do is create a completely new custom module with two color picker fields. Then, you can apply the background using inline style, for example: style=“background-color: {{ module.bg_first_col.color }}”.
Since you’ve already created the section in the email editor, I would suggest copying the entire HTML code of the section using the developer tool and pasting it into the new module. This way, you can save some time.
Hope this helps.
Regards,
Gracjan