Yellow baby vomit?? Warning picture!

My daughter is 3 months old and in the middle of the night she vomited a yellow liquid all over her crib and herself. She wouldn’t feed well about 30 minutes before this, but after she’s back to sleep and seems ok. No fever, no fussing, just randomly threw up yellow. What does that mean? Whys it yellow? Do I need to be worried? I posted a picture to show how yellow and how much there was.