你是我路过的倾城时光我是你观望的璀璨烟火
[nĭ shì wŏ lù guò de qīng chéng shí guāng wŏ shì nĭ guān wàng de cuĭ càn yān huŏ]
You are my fleeting beautiful moments; I am your observed bright fireworks. It conveys mutual impact yet transient presence: being impactful and beautiful at one moment but disappearing soon after.