She's got a line of navy pencil under her eyes with a taupe or brown on the top lids so she gets a little hint of blue that's tempered with the more expected shade up top. It's kind of sexy in an off-beat way. And it makes your eyes stand out--always a good thing when it comes to flirting.
Want to give it a try? These pencils would do the trick.
Related: A Soft, Subtle Eye Makeup Look You Can Steal From Natalie Portman