浪荡少女懵懂少年
[làng dàng shăo nǚ mĕng dŏng shăo nián]
Refers to rebellious teenage years filled with confusion and adventure, contrasting yet complementary experiences between sexes during adolescence. For girls ('少女'), being carefree (浪荡 - làng dàng), and for boys ('少年') feeling clueless and unversed (懵懂 - měng dǒng).