Excuse me, I was reading about Arculus and I came across the term 'cold storage crypto wallet.' Could you please clarify if Arculus is indeed a cold storage crypto wallet? I understand that cold storage wallets are designed for maximum security by keeping the private keys offline, but I'd like to hear your expert opinion on whether Arculus falls under this category. Additionally, if Arculus isn't a cold storage wallet, could you elaborate on the security measures it employs to protect users' digital assets?