薄荷沁凉烟花已散
[bó hé qìn liáng yān huā yĭ sàn]
Peppermint Coolness and the Fireworks Are Already Gone. This describes a cool yet ephemeral moment, much like how a peppermint taste fades quickly. Likewise, beautiful and joyful moments (like watching fireworks) will pass, evoking a sense of nostalgia.