Really cool idea and well executed! I have the benefit of having a keyboard with volume buttons. Some passages could be quite difficult without these. I love how you described the gameplay elements instead of directly naming them, like "Dinos have strong feet" instead of they can walk on spikes. A little, lovely detail. In some areas the camera frame was a bit too small to see everything important (I had to jump down to get a coin only hoping not to touch a dino).
Overall a really nice game, good job!