Column bottom alignment

I have two blocks side by side acting as two columns side by side filled with text in each one.  I use a site background that is not white (#323232), the columns/blocks in this case are set to white (#ffffff).  At various sizes of browser scaling, one of the columns gets shorter/longer than the other due to the text scaling in the blocks and then the dark site background shows through.

You can see it below right when the browser size is scaled smaller. If I keep making the browser smaller the dark space may then flip to the other column.

Just wondering if anyone can assist in finding a solution to this problem.  Thanks.