Due to an issue with the Steam store page, you can temporarily purchase the game using the link below.
https://store.steampowered.com/sub/1514075/
or
BLACK PANDA BUNDLE:
https://store.steampowered.com/bundle/90851/BLACK_PANDA/
Source: Steam Community (opens in a new tab)
Build and release context
Recorded Steam release date:
Within one calendar day of this post (UTC). The listed date does not establish an exact launch time.