Custom vivarium doors- looking for suggestions

I'm planning on building a large vivarium for amphibians. The base, which is already built, is constructed of wood, with a pond liner. I am now building the upper sides, which will be glass with (wood or metal) framing.
I am having trouble figuring out what to do for doors. I prefer sliding doors, made of tempered glass. Think shower doors, only smaller. I can have these custom made simply enough; however there would be gaps between the doors, through which tiny frogs and insects could escape. And, if I use rollers under the doors, there would be potentially creating more gaps.
Any suggestions?
I'm also looking for ideas to decorate and/or plant the back wall.