I don't know if Zeit Now (while really cool!) would work for NodeBB... NodeBB is a web application, and does lots of stuff in the background that relies on a server running. To have a service that spins up whenever a request comes in would be much too slow, if only because that first spin up would take many seconds!
@spwolf unless you applied custom css on your site to make the icons and text smaller, there shouldn't be any difference. Persona theme is used as is on this site. I am sure that there is no custom css applied here.