Hey! I just spent 20 minutes playing your game and I like it a bunch!
I really like the art style and I think it fits well with the overall theme of your game. I also really like the animations for the lava. I also thought that the difficulty was just right, the first level took me a couple of tries but I got better at it quickly and could go through it faster.
That being said, I wish that there was some sort of a checkpoint system so that once I reach the second level I don't have to keep restarting from the beginning, because that felt tedious and makes me feel like there's a lot of the game that I can't check out. I think that a cool feature to have would be for the player to kill an enemy if they land directly on top of them.
However, the quick screen transitions felt appropriate and satisfying enough to keep me playing. Most importantly, the controls feel snappy and responsive, which is something that I love in platformers.
I also published my first game today and it's also a platformer where the player tries to escape from lava. I'd love it if you checked it it out and gave me feedback too :). Keep up the good work!