I there,
I’m not sure you can achieve this with padding and regular column element.
You might want to try work with a flex box instead.
I have a container set to display: flex. then inside the container, you have one div “left” then a div “separator” and finally a div “right” that are disposed next to each others. What you could do is set layout of the two div “left” and “right” to expand, wheread the “separator” would have a let’s say a width of 20px for example.
Here is a read-only link that could maybe help you.
There might be an easier option, but I wouldn’t alyway work with columns to layout things out.
humm that might work. My problem is trying to wrap my brain around this new software ( I know how to code and still use tables/cells/paddings etc) What I ended up doing was using background color on the two end columns, then , in the center column selecting the text box and just adding bckg color to that ALONE and adjusting the padding on either side and bingo… 
It displays fine though it kills me to do it that way.
