A simple web-based game that features a player and two enemies
- 1 player
- 2 enemies moving up and down with different speeds
- press ⬅️➡️ to move the player [hint: add event listener for keydown and keyup]
- 1 goal at the right side of the box
- when player and enemy collide, game over
- when player reaches goal, level complete
- every level, increase speed of enemy
