Hi there,
Bernina in there refers to the first stop, Hotel Bernina, see e.g. https://files.livigno.eu/pdf/servizi/orari_bus_verde_sett2017_v2.pdf
Just "Linea Verde" would be a bit too short, I think, since there are two routes. Maybe change "Bernina" to "H. Bernina" or "Hotel Bernina" in the name? H. as abbreviation for Hotel is used commonly in the buses / timetables in Livigno.

Regards, Dennis