黯然一笑很倾国嫣然一笑很倾城
[àn rán yī xiào hĕn qīng guó yān rán yī xiào hĕn qīng chéng]
'A smile amidst sadness can shake the whole country; A bright laughter can captivate the city.' It depicts powerful charms that even fleeting facial expressions carry profound impacts based on ancient beauties' stories.