What chain is Kujira on?

Could you please clarify which blockchain Kujira is currently operating on? I'm interested in understanding the underlying technology and ecosystem that Kujira is a part of, as it's crucial for assessing its potential and compatibility with other projects. Is Kujira built on a popular, established blockchain like Ethereum or Binance Smart Chain, or is it leveraging a lesser-known or proprietary blockchain? Your insight would be greatly appreciated.