青春漫不经心
[qīng chūn màn bù jīng xīn]
This online name conveys a sense of casualness and nonchalance towards youth. 'Youth' represents the most energetic, carefree, and passionate time in life; while '漫不经心 (carefree)' suggests an attitude of indifference or lack of attention, which may imply the tendency of many people to take youth for granted.