first time chicken owner! is my chicks vent okay?

We just got our chicks yesterday. I've been keeping a close eye on this one because a lot of the other plymouth rocks in the brooder at the store had pasty butt. So far no pasty butt, but I unnoticed today her vent was more noticeable than yesterday. None of the other chicks look like this. At the moment it's not red, but i just want to make sure she's okay!! I'm learning I'm a very anxious chicken keeper - very new to this.

Anything I should watch for or do to prevent any issues?