What chain is Mintlayer on?

Excuse me, could you please clarify for me which blockchain network does Mintlayer operate on? I understand that Mintlayer is a platform that offers various decentralized finance solutions, but I'm curious about the underlying technology that supports it. Is it built on a popular blockchain like Ethereum, or is it a unique and proprietary network? I'd appreciate any information you could provide to help me better understand the infrastructure behind Mintlayer.