"Heavenly Blue" served as the opening theme for the 2014 anime series "Aldnoah.Zero", composed by Hiroyuki Sawano with Kalafina's vocals.
"Heavenly Blue" is a signature song by Japanese vocal group Kalafina, known for their ethereal harmonies
and frequent collaborations with anime composer Yuki Kajiura. The track combines elements of J-pop
with orchestral arrangements, characteristic of the group's style.
