class Bullet extends Entity { constructor(x, y) { super(x, y, 0.001, 0.02); this.element.className = 'bullet'; } update() { if (this.alive) { this.y -= 0.01; if (this.y < -0.1) { this.destroy(); } for (let cloud of clouds) { if (this.isOverlapped(cloud)) { cloud.destroy(); this.destroy(); } } } } } class RainDrop extends Bullet { constructor(x, y) { super(x, y); this.element.className = 'raindrop'; } update() { if (this.alive) { this.y += 0.01; if (this.y > 1.1) { this.destroy(); } else if (this.isOverlapped(shootingPad)) { gameOver('Game over'); this.destroy(); } } } }