Little Square in unit icon

[maxfra]

Sorry for this noob question, but what is the litte square on the bottom left side of a unit's icon? It may be green, yellow or red, but does it mean? Is it bound to supply or something else?

Thanks.

Max.

[Herode_2]

Yes it is bound to the supply status : green is OK, red is...
You can also check the supply layer to see the co-incidence.

[PDiFolco]

It means how much supply the unit will get or not on the next turn : green is ok, red is "no supply" or very few, yellow something inbetween - I don't have the exact figures. Anyway note that a unit, even red, can still have supply stored and move/fight normally for 1 turn, but after that it will decrease.