他的冷瞳她的暖眸
[tā de lĕng tóng tā de nuăn móu]
This refers to 'His cold eyes and her warm gaze' using the color or look of someone’s eyes (here described as either cold or warm) to reflect a personality trait. One could interpret this as contrasting temperaments of two lovers where she brings warmth into his colder, distanced heart.