Coolant leak?

I have 2002 Pontiac Montana and during the day (when I go to work) I park my car slightly unlevel where the passenger side is a little bit higher than the driver side.

Recently, I noticed some redish/pink spots on the snow. It was located at the front/passenger side (i.e. the higher side when parked) and close to the tire. Could it be coolant leak or brake fluid?

I checked the fluids and it seems that the level of coolant at the reservoir a little bit down but still okay.

Any advise on this matter?

Thanks.