Screen Fit options??

hi guys, im using one of those Android mini PCs,
the Tronsmart Prometheus box.

when im browsing the web using DOLPHIN BROWSER,
im using the desktop mode to always get desktop websites and not mobiles but,
Lets say i go on facebook login page,
it looks way too zoomed in, its not like on my windows PC.

I checked in the options and stuff but,
nothing i tried made the facebook login screen take the whole screen..
it always looks zoomed in no matter what,,,
and im not talking about the FULL Screen feature here if u know what i mean,

ANy idea how to fix this?

thanks