Skin darkening around the eyes, often called periorbital hyperpigmentation, is very common and completely harmless. To help lighten the area, you can use gentle creams containing active ingredients like Vitamin C, Kojic acid, Niacinamide, or Azelaic acid. Applying a daily broad-spectrum sunscreen with zinc oxide is also crucial to protect this sensitive skin from further tanning. Additionally, ensure you get adequate sleep and stay hydrated. Because the skin around the eyes is highly delicate, I recommend consulting a dermatologist for a personalised evaluation before starting any strong medicated treatments.