素颜易泯红装易卸
[sù yán yì mĭn hóng zhuāng yì xiè]
Roughly translating to 'Plain face wears off easily, Red makeup fades readily'. It refers to the contrast between natural beauty ('plain') that easily goes unnoticed against adorned appearance which can be removed ('unadorned beauty is lost easily whereas artificial looks can be changed'), suggesting superficiality vs true self in societal perceptions.