As long as it is just light and the temperatures don't exceed roughly 82°F I would say you are fine. The heat mats however, do you have a thermostat for the UTH? Those temperatures must be on point for good digestion.
Here's a temperature guide for all leopard geckos as measured with the probe of a digital thermometer (and controlled by a thermostat):
•88-92 F (31.1-33.3 C) ground temperature right underneath a leo's warm dry hide
•no greater than 82ish F (27.8ish C) air temperature - 4 inches above ground on the warm end
•no greater than 75 F (23.9 C) air temperature - 4 inches above ground on the cool end
I believe [MENTION=8562]acpart[/MENTION] has made a 2 level terrarium! Yours looks pretty good, I wondered if a stool would work as a second level or some sort of foam cutout. Maybe even wood, four beams with a lizard ladder or ramp to access a platform.
Good luck!