Mila Kunis hike tights Hollywood Hills

What a difference a day makes!

Less than 24 hours after she got all glammed-up to attend the premiere of her newest flick, Ted, Mila Kunis traded her turquoise Christian Louboutins for tennis shoes as she headed to the Hollywood Hills to take a hike with some friends, on Friday afternoon.

The brunette beauty has recently been seen getting cozy with her That 70's Show costar Ashton Kutcher, and we even spotted the pair taking a romantic motorcycle ride through LA last week. Kunis was also recently seen leaving the actor's house after a sexy sleep over.

Sounds like things are heating up for the former onscreen couple!