Run static website with password auth in cloud

I have a simple one. Static website available after login - easily build and running on nginx.

But it seems to me cumbersome to server static web with small amount of connections (few per day) and spent a hours to set properly and maintain virtual machine during the lifespan of this project.

I use mostly GCP and consider their load balancer, or buckets made for static content, but none of this is able to give you a chance to auth users with passwords.

Do you have any tip for this? Provider is not concern or some kind of serverless with a pay as go will be perfect in my situation.

Thank you for your time