I need to add a margin on a fixed footer in a web page in print media. I made the footer fixed by adding fixed position but could not add the margins. The fixed footer overlaps with the content above.

The footer needs to have a minimum margin of 20 mm at the top so that it doesn't collide with the content above and a margin of 20 mm at the bottom.
Here is the demo page : https://storage.googleapis.com/cwsogbl/index.html
Can anyone help with this?
The distance to the bottom should be adjustable using a
bottom: 20mmsetting instead ofmarginon the fixed-position footer. The free space above can probably be done with a relatively largepadding-bottomon thehtmlorbodyelement (inside the @pmedia print rules) to create a free space under the footer at the end.