Fully local nameservice - eviltoast

I’m finally starting to install local web apps that my wife/kids would be interested in, and I know it has to be super easy or they’re never going to go near it. Most everything is running on my Synology on different ports, with absolutely nothing exposed to the outside world, and I’d like to run local DNS and proxy so everything is available LAN-only with an easy hostname - plex.local, paperless.local, etc. (If we want remote access I’ll just run Tailscale.) I’m already running PiHole, and I’m assuming if I poke around I can add local names in there, but has anybody else that’s done this have any suggestions for setting things up?