How to "contain" my cats for wedding

I need a way to block off a portion of my house - from the middle of a hallway back - to keep my cats safely contained, but floor to ceiling gates for cats don't seem to exist. Any thoughts? Here are more details...

I have two cats and an upcoming wedding that will take place at my home. Because we've only recently bought this house, many of the guests at the wedding will want to come in to see the place, PLUS, we will have several vendors who will need to access the inside. The cats are not allowed outside.

My fear is that one - or both - of the cats will slip out, unnoticed, when someone (vendor, child, me in my big dress, etc...) comes in or out. Also, of the two doors that would be used, one doesn't shut without you pulling/pushing it, and the other is a slider, so the chances of a cat escape are high.

I don't want to shut them both in one room for the entire day - my little cat needs her "safety" spot in the bedroom, and they both need access to the food and litter boxes in the room next door.

Has anyone seen anything that could work? Any kind of gate or any ideas on what I could rig up for the day so I won't be stressing about my cats?

Any thoughts are appreciated!! Thanks!