2 Desktops, 2 different font sizes?

Hello.

I’m using 2 desktop system for Anki. One with an external monitor with 4k resolution, and one laptop in which the resolution is lower. The 4k got 70px font size on one template, but that’s way to huge for the laptop version. So I tried this:

especially the part with

@media (max-width: 4000px) {
  font-size: 70px;
}

@media (max-width: 2000px) {
  font-size: 30px;
}

but I can’t make it work. Is there any other possibility?
I can adress phone and ipad with the .iphone and .ipad prefix. But how can I address 2 different desktop systems?

thanks in advance

Try a smaller number like

@media (max-width: 400px) {
  .card { font-size: 40px; }
}

Then as you resize the Anki window, you should see the font change.