The only clear terminology is "long" or "short" tee (or "middle", etc.) "Junior" or something can clarify for additional, even shorter tees.
As far as colors, we all get used to certain color schemes based on places we play. E.g. Houck courses with Red=short, Blue=long, White=intermediate, Gold=longer long (that may not always be available) are well known and may thus set some kind of standard.
But even here in Pittsburgh, Deer Lakes and Moraine are both top 20 courses on DGCR, maintained somewhat by the same Pittsburgh DG association, and don't bother using the same scheme. Deer Lakes uses the Houck-esque Blue-White-Red, while Moraine uses Gold-Blue-Red. I don't see that as a knock on either, though I did get confused when registering for a tournament, when I was confused about which layout was "blue."
Just make sure you stay consistent within the same course, and you'll have no complaints from me.