Literature Reference: 暮雨旌旗湿未干，胡尘白草日光寒。—— 《鼓吹曲辞 凯歌六首 六》 In the evening rain, the banners are still wet, while the dust of the barbarians and the white grass are chilled by the cold sunlight. Source from 'Chui Ge Liu Shou Liu'.
雨: The life-giving rain that nourishes all things.
旗: Smooth progress and triumph pave a favorable path for future advancements.
Meaning: The banner still flies in the rain, symbolizing unwavering resilience and the hope of victory.