There’s no denying it: Billie Eilish is an icon. From her oversized wardrobe to her catchy anti-pop bangers, this 17 year old singer-songwriter is cooler than cool. And so is her ever-changing blue-hued hair. And while she said goodbye to her signature color earlier this month, opting instead for some neon green roots, we can’t get over how effortless and edgy she made this classic color trend. In honor of her iconic locks we’re highlighting her best blue hues, from those deep dark shades to frosty pastels and everything in between.