In the page “contracts” unders “areas of practise” I have two lists and I need to add a line to separate the two. I would like to create a list that spans from the top of the text to the bottom of the last item in the list. If I add a border on the column the line spans beyond the text.
Not sure if I correct understand your problem. By your link I see the line there between 2 columns. Did you find out how to do what you want or it is not that line that you would like to have?
I would try make 3 columns row there (instead of 2 columns), middle column with minimum width. Inside middle column I would add div with 1-5 px width and put border on it. At least it is easier to move and change such “line”.