If transactions are decentralized like you say, than are wallets used by customers with their own keys, or they are centralized and part of Bridgoro exchange?

I wanted to check this for myself so I created account at your exchange, but there is some bug that constantly refreshes page, so I can't open anything, including menu.

If transactions are decentralized like you say, than are wallets used by customers with their own keys, or they are centralized and part of Bridgoro exchange?
I wanted to check this for myself so I created account at your exchange, but there is some bug that constantly refreshes page, so I can't open anything.