Welcome to FF! Here is a good article to help care for your White's: Frog Forum - White's Tree Frog Care - Litoria caerulea. You want day temps at 85F and can drop that to 75F at night.

For nighttime heat can use ceramic heat emitters (no light), black "moonlight," or infrared bulbs. Can control those with a manual dimmer "rheostat" or automatic thermostat. Lamps do reduce humidity so watch it stays around 50-60%. If using heat mats or similar, those have to be used outside enclosure side (not underneath). Hope this helps and good luck !