What network is Loopring on?

Could you please elaborate on the underlying network that Loopring operates on? I'm particularly interested in understanding the blockchain infrastructure that supports its decentralized exchange functionality. Given the significance of scalability, interoperability, and transaction speeds in the cryptocurrency ecosystem, I'm wondering if Loopring leverages a popular layer-1 chain or if it's built on a layer-2 solution to enhance these key metrics. Additionally, I'm curious about the potential benefits or trade-offs of this particular network choice for Loopring's users and ecosystem.