Hi Deac77,

Screen tops ( from big box pet store ) they are available to fit most standard fish tanks then use glass or plexi ( cut to fit) on at least 3/4 of the screen lid to hold the humidity in.
I use glass( easier to keep clean) 'glued' in w/ aquarium sealant to the inside of the lid so they can climb on it when the tank is used vertically.

Pic here of a 10 gallon converted lid:
the lid is off in this 1st pic to the left ----- leaning against another tank

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below --glass on the inside of the screen ( this houses tree frogs that will climb on the glass front)

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