Is ETH fully proof-of-stake?

Excuse me, I was reading about the Ethereum network and came across the term "proof-of-stake." I understand that it's a consensus mechanism, but I'm a bit confused about its current status within the ETH network. Can you clarify whether Ethereum has fully transitioned to proof-of-stake, or is it still a hybrid model with proof-of-work? I'm interested in understanding the timeline and milestones achieved so far in this transition process. Thank you for your time.