I have no time to experiment right now (but I will, after work), but the https://www.sitepoint.com/css-printer-friendly-pages/ article might be useful, along with the trick above by @dpoulton: it looks like you can surround this CSS with @media print to show it only when printed, and if you use @print, maybe you can get this to repeat on each page.
Again, to try, I never tried print-specific CSS before.