曾经的那段青春如此潇洒曾经的那段青春如此放肆
[céng jīng de nèi duàn qīng chūn rú cĭ xiāo să céng jīng de nèi duàn qīng chūn rú cĭ fàng sì]
It refers to those days of youthful exuberance when one was free, carefree, and indulged recklessly. It's a nostalgic ode to the wild and free spirit of youth.