It's "Black and White Diary"

The commonly used background music in Hei Chen's Blank Diary is the song "Blank Diary" sung by Pan Qianqian. The main lyrics are "I often remind myself that I remember missing you, but it's blurry and I can't get close. I can't go back a long time ago, but I still lied to myself. It took me back to the past and it's so white that I can't see clearly."

《 The original singer of the song "Black and White Diary" is Pan Qianqian; the lyricist is Pan Qianqian; the composer is Pan Qianqian; the arranger is Yan Xiaojian; the agency is Beijing Zhongshi Xinghe Culture Media Co., Ltd.; the producers are Pan Qianqian and Ah Rong.