Thanks for the quick reply!
This does work, in a way, but the problem is that now on smaller screens you have a vertical scrollbar even though all that extra space is empty! I found this:
https://pixelsvsbytes.com/blog/2011/09/sticky-css-footers-the-flexible-way/
But I dont’t know exactly how or if this can be implemented to your current theme structure. Any thougths?
Thanks again!