Yes, light gray is perfect. Nice white trim and tile, I assume are already in place.

Pick a paint you like.?shower curtains can be easily replaced.

Maybe just a sand color for the paint and then use other green and white accents for the rug or some towels? Or throw in a darker brown accent color as well. Are the tub, toilet and sink all white? Are the tiles white or another color? Are there curtains or a shade? Is there a wood tone vanity (hopefully it would be darker to contrast with the sand colored walls). All of this would matter.

I'm having a hard time deciding. Maybe a light gray?