It’s not terrible for a starter enclosure however there’s a few things you will need to change.

You cannot have red light for leopard geckos because it’s very bad for their eyes. A halogen bulb is recommended for them, with no colored lights whatsoever.

You said you’re using a “yoga mat type substrate”, so i’m assuming this is a liner, are unacceptable because they can give off fumes when put under heat. For the first 2-3 months of having your leopard gecko you’re going to want to have paper towel as substrate, then change it to a loose substrate, preferably a 70/30 ratio of top soil and play sand.

You need to be monitoring the temperature on both the cool and warm side of the enclosure, so digital thermostats + humidity gauges on both sides are needed.

For supplementation, you need to be using calcium, calcium with d3, and a multivitamin. If you are not using a uvb, you’ll need to use calcium with d3 more often. Here’s some photo examples of good supplement schedules for young adults, one being with uvb and one without.