I found her blond hair horrible and did not fit her at all. They seemed to have lighten her skin tone as well to make her pass as white, which made the whole thing artificial. It felt as if they wanted to do everything to make Jennifer ugly. And it's pretty sad considering Jennifer is quite a beauty.
Which reminds of the beautiful brunette Lena Headey who plays Cersei in Game of Throne where they did something similar to her by lightening her skin tone and dye her her hair blond, which destroys her beauty.
I have to admit personally I find blond ugly and blonds ugly too.

Perpetual coolness is the vampire's curse. - Mick St. John in Moonlight

She is so beautiful in this movie. I honestly think she is one of the most beautiful women in movies. There is something so natural and earthy about her beauty. she and Jim Caviezel are two of the prettiest people I have ever seen and to have them both in one movie was a treat for the eyes.

Sorry, but her skin tone also seemed lighter than normal in an apparent attempt to match the haircolour which also made her makeup look somewhat pasty and artificial as well. (I think some of the haircolour companies that recommend one or two shades lighter or darker than the natural shade are spot on.)
In contrast Jim Caviezel's appearance featured dark hair framing a lightly tanned skin tone which blended seamlessly with subtle darker undertones which may have added to his aura of class and mystery.
Natural is best.

That's true about her hair color but it still looked really nice on her

Her beauty and athletic proportions were top notch as usual, however I thought her blonde hair with its dark roots was a distraction and looked very artificial.

she look good in 'out of sight' as well.