Your squats look really good. There's no significant separation between your heels and the floor; it just looks like your weight is drifting toward the front of the foot as you reach the bottom position.
I don't see much of an issue with ankle or hip mobility although it doesn't hurt to do some of those mobility exercises before your training.
But if you're seeking perfection, keep playing around with your stance. For example, try rotating your toes out some. Also, drive your elbows up out of the hole. This will help keep the bar from pulling you forward and keep your weight distributed correctly. If you're having problems raising your elbows any further, stretch out your lats and triceps before and in between sets.