How To Put A Min-height In A Relative Class Css?

I'm actually designing my website, it's going to be a one HTML page using javascript to switch between divisions. I'm using a wrap division where my banner/header, text container a

Solution 1:

Since #wrap is a positioned element and you've already applied bottom:0 for the footer, all you've to do is Simply apply position:absolute to the footer, so that it'll stay at the bottom of #wrap regardless of the content inside it.

Demo

Side note: you also might want to apply padding-bottom to #wrap equal to the height of footer so that content won't get hidden behind the footer