Project: canvas
Task (challenging): Periodically spawns enemies at random vertical positions on screen's right edge, generate one per second, stores in 'store.enemies', with maximum 10 simultaneous enemies. Enemies move to left at constant horizontal speed 6 while having random initial vertical velocity (range -0.5,0.5 ). On collision with bird, reduces player life. Enemy sprites use mirrored and color-inverted version of 'assets/bird.png', pre-rendered using offline canvas for performance. Note: Do not forget to implement the new method.