What rhetorical device is used to fly freely as light as a dream, and the rain as fine as sorrow?

Outside the window, the flowers are dancing freely, just like in a dream, the rain is falling and drifting aimlessly, like melancholy.

The rhetorical methods used are duality and metaphor.

Duality: poetry is neat and neat;

Metaphor: flying flowers are as light as dreams, and silk rain is as thin as sorrow.

Huanxisha Momo Qinghan Shang Xiao Building

Dynasty: Song Dynasty

Author: Qin Guan

The desert is light and cold, with small buildings. Silver hooligans are like poor autumn. Looking back at the screen, the light smoke, the flowing water, the mood is faint.

Outside the window, the flowers are dancing freely, just like in a dream, the rain is falling and drifting aimlessly, like melancholy. Look again, the curtain of jewelry hangs on the silver hook at will.