But which definition of "Point" should be used? It's ambiguous (see https://en.wikipedia.org/wiki/Point_(typography)#Varying_standards https://en.wikipedia.org/

But which definition of "Point" should be used? It's ambiguous (see https://en.wikipedia.org/wiki/Point_(typography)#Varying_standards https://en.wikipedia.org/wiki/Point_(typography)#Varying_sta... ). At this point, if you demand length equality, use well defined absolute units (i.e. mm, cm, in). However, you've going to have to make some difficult decisions between using absolute units and small-screen support. Relative units permit dynamic rescaling but in so doing one has to give up the explicit length equality demand. If you really want to, you can use device/media queries and varying stylesheets to get around this; but for all that is holy, please don't demand 12pt be 12pt everywhere -- we can't even all agree on what a point is without (implicit and unreliable) context.