Google any online guide to blue eye beauty looks and you’ll find a myriad of orange-tinged eye shadows and liners, from shiny metals like copper and bronze to earthy tones like mahogany. If you’ve ever asked yourself why, it’s because these tried-and-true shades follow the rules of color theory. Blue and orange are true compliments, meaning they stand out most when paired. But what about the unexpected color combos that add a little sparkle to cobalt eyes? We turned to some of the nation’s top makeup artists to ask about the best-kept secrets behind helping blue eyes shine. Scroll through to find out!