I am having the hardest time trying to figure out this (should be) simple css:

Website is here: http://mibsoftware.us/fct/index.php

I'm simply trying to get my #leftcolumn and #maincolumn to be inside the #content_container, yet whatever I'm doing isn't working at all. I'd like for the #content_container to be a dynamic height since the height of #leftcolumn and #maincolumn change depending on the page you are on.

From the framework of my css it should work fine, so I must be missing something in my .css file declaring these divs. Any help would be greatly appreciated, as this will be a great learning experience for me.