I saw this video on levitating a denser liquid on less dense air by vertical shaking.

But I couldn't understand some points in the video.

1 : Why didn't the air below the liquid mix up with the liquid since it is under extreme pressure due to the weight of the liquid ? If it shakes regularly wouldn't the liquid Ever fall ?

2 : Also how did the liquid levitate at 0:37 ? Since the air was in the upper region of the tank , so why and how did that layer of air came at the bottom of the tank and caused the liquid to levitate ? Is it due to certain frequencies of vibration ?

Help me with this.