The animation was produced by Shaft under Shinbou Akiyuki's direction. Given its quality, overall this is a highly recommended anime for watching.
Here is Opening sequence of cut 40 from the opening. The full opening is under the storyboard of Umetsu Yasuomi. He is also the animation director. The layout artist of Cut 40 is Toshio kawaguchi, a big name in Studio Ghibli,also worked in EVA, Ghost in the shell, JIN-ROH etc.
Cut 40 is corresponding to the lyric “Down Townへくりだそう” which is 1:06 of the song. The action Hotori Arashiyamahoding a sweep and quick turn around. Roughly 3 seconds with 22 key frams. Correction sheet was done by Umetsu Yasuomi himself but unfortunaly I scanned as black and white.




Full Opening https://www.youtube.com/watch?v=zxQqb_ULBjk
The singer is Maaya Sakamoto, a very talented singer and Seiyu. Her famous op song includes Kiseki no Umi,hemisphere,tune the rainbow,Yubiwa etc,etc... Yeah, really like her songs.
The song is actually a cover of Tatsuro Yamashita’s famous song "Down town". Same name.
Highly recommend his original version as well
https://www.youtube.com/watch?v=FlwXdLCUG1A