Who pays gas fees on Rarible?

I'm curious to know, who exactly is responsible for paying the gas fees on Rarible, the popular decentralized marketplace for digital collectibles and non-fungible tokens (NFTs)? Is it the buyer, the seller, or is there a different mechanism in place that determines who bears the cost of these transaction fees? Understanding this aspect of Rarible's platform is crucial for users looking to navigate the world of NFTs and make informed decisions about their transactions.