Until she’s fully litter trained, she shouldn’t have any grass baskets, pet beds, or anything similar to lay on. For some reason, some bunnies end up thinking that anything remotely litter box-shaped is a great place to soak with pee.
The next time she pees on her cage floor, mop a little bit of it up with a paper towel and put it in her litter box. Put a few fresh poops in there, too. Make sure the rest of her cage is clean before you do this! This is the main way that I trained (and, after bonding them, re-trained) both of my rabbits to use the litter box.
Just stay patient! She’ll get the hang of it before you know it.
She’s a little too young for it right now, but when she’s a few months older, you should consider getting her spayed by a good rabbit vet. From what I’ve seen, unspayed rabbits generally can’t be fully litter-trained. Also, spaying rabbits eliminates their chance of getting uterine/ovarian cancer, which affects up to 70% of female rabbits.
If the pee is a slightly orange red color, chances are it’s just red pee. Some bunnies get it from certain types of fruits and veggies. As long as it’s not diarrhea and it doesn’t look like blood, there’s nothing to worry about. 