[Sunshine]

Green would be antifreeze. Open the radiator by loosening the cap located front center of engine opening and see if it's full. If you can see the green stuff you have enough to get it to dealer or repair shop.

How much was there? If it was just a small puddle and because it's so cold out you probually can make it to a garage. Watch your engine light, if it goes on pull over immediately and turn engine off (but I don't expect this to happen)

If it was blue, it would be window washer fluid, no big deal.

Either way, doesn't sound expensive.