Due a Cludflare issue, the site was temporary unavailable. Thanks to the decentralization – as the team said it in a tweet – there are several other options to keep trading.
Use another IPFS gateway
Run it locally
You can trade trought MetaMask or other Ethereum wallets
You can trade trought aggregators
When a centralized service become unavailable, there is no second option. Btw the issue was fixed in the late night same day.