var Explosion = Container.expand(function () {
	var self = Container.call(this);
	var explosionGraphics = self.createAsset('explosion', 'Explosion Graphics', .5, .5);
	self.animationDuration = 10;
	self.tickCount = 0;
	self.on('tick', function () {
		self.tickCount++;
		if (self.tickCount > self.animationDuration) {
			self.destroy();
		}
	});
});
var ParallaxBackground = Container.expand(function (layers, speed) {
	var self = Container.call(this);
	self.layers = layers.map(function (layerInfo) {
		var layer = self.createAsset(layerInfo.id, layerInfo.description, 0.5, 0.5);
		layer.speed = layerInfo.speed;
		self.addChild(layer);
		return layer;
	});
	self.move = function () {
		self.layers.forEach(function (layer) {
			layer.y += layer.speed;
			if (layer.y >= 2732 + 1000) {
				layer.y -= 2732 * 2;
			}
			layer.x = 2048 - layer.width + 1000;
		});
	};
});
var HealthPickup = Container.expand(function () {
	var self = Container.call(this);
	self.creationTime = LK.ticks;
	var pickupGraphics = self.createAsset('healthPickup', 'Health Pickup', .5, .5);
	self.restoreAmount = 10;
	self.move = function () {
		self.y += 2;
	};
	self.applyToHero = function (hero) {
		hero.health = Math.min(hero.health + self.restoreAmount, hero.healthBar.maxHealth);
		hero.healthBar.updateHealth(hero.health);
	};
});
var HealthBar = Container.expand(function (maxHealth) {
	var self = Container.call(this);
	var background = self.createAsset('healthBarBackground', 'Health Bar Background', 0, 0.5);
	var foreground = self.createAsset('healthBarForeground', 'Health Bar Foreground', 0, 0.5);
	self.setMaxHealth = function (maxHealth) {
		self.maxHealth = maxHealth;
		self.currentHealth = maxHealth;
	};
	self.updateHealth = function (currentHealth) {
		self.currentHealth = currentHealth;
		var scale = currentHealth / self.maxHealth;
		foreground.scale.x = scale > 0 ? scale : 0;
	};
	self.setMaxHealth(maxHealth);
});
var Hero = Container.expand(function () {
	var self = Container.call(this);
	var heroGraphics = self.createAsset('hero', 'Hero character', .5, .5);
	self.healthBar = new HealthBar(100);
	self.healthBar.x = 10;
	self.healthBar.y = 10;
	LK.gui.topLeft.addChild(self.healthBar);
	self.speed = 5;
	self.health = 100;
	self.healthBar.setMaxHealth(self.health);
	self.healthBar.updateHealth(self.health);
	self.move = function () {
		if (self.y + self.speed > 0) {
			if (self.y + self.speed < 2732) {
				self.y += self.speed;
			}
		}
	};
});
var Enemy = Container.expand(function () {
	var self = Container.call(this);
	var enemyGraphics = self.createAsset('enemy', 'Enemy character', .5, .5);
	self.baseSpeed = -3.6;
	self.move = function () {
		self.y -= self.baseSpeed;
	};
});
var HeroBullet = Container.expand(function () {
	var self = Container.call(this);
	var bulletGraphics = self.createAsset('heroBullet', 'Hero Bullet', .5, .5);
	self.speed = 12;
	self.move = function () {
		self.y -= self.speed;
	};
});
var EnemyBullet = Container.expand(function () {
	var self = Container.call(this);
	var bulletGraphics = self.createAsset('enemyBullet', 'Enemy Bullet', .5, .5);
	self.baseSpeed = -12;
	self.move = function () {
		self.y -= self.baseSpeed;
	};
});
var Game = Container.expand(function () {
	var self = Container.call(this);
	var backgroundLayers = [{
		id: 'backgroundFar',
		description: 'Far Background',
		speed: 0.5
	}, {
		id: 'backgroundMid',
		description: 'Mid Background',
		speed: 1
	}, {
		id: 'backgroundNear',
		description: 'Near Background',
		speed: 1.5
	}];
	var parallaxBackground = self.addChild(new ParallaxBackground(backgroundLayers, 2));
	var hero = self.addChild(new Hero());
	var enemies = [];
	var heroBullets = [];
	var enemyBullets = [];
	var score = 0;
	var scoreTxt = new Text2('0', {
		size: 150,
		fill: "#ffffff"
	});
	LK.gui.topCenter.addChild(scoreTxt);
	hero.x = 200;
	hero.y = 2732 / 2;
	LK.on('tick', function () {
		var LEFT = 37, UP = 38, RIGHT = 39, DOWN = 40;
		LK.stage.on('move', function (obj) {
			var touchPos = obj.event.getLocalPosition(self);
			hero.x = touchPos.x;
			hero.y = touchPos.y;
		});
		if (hero.x < 0) hero.x = 0;
		if (hero.x > 2048 - hero.width) hero.x = 2048 - hero.width;
		if (hero.y < 0) hero.y = 0;
		if (hero.y > 2732 - hero.height) hero.y = 2732 - hero.height;
		parallaxBackground.move();
		hero.move();
		self.children.forEach(function (child) {
			if (child instanceof HealthPickup) {
				if (hero.intersects(child)) {
					child.applyToHero(hero);
					child.destroy();
				} else if (child.y > 2732 + 50 || LK.ticks - child.creationTime > 300) {
					child.destroy();
				}
			} else if (child instanceof Explosion && LK.ticks % 5 === 0) {
				child.destroy();
			}
		});
		for (var i = 0; i < enemies.length; i++) {
			enemies[i].move();
			if (hero.intersects(enemies[i])) {
				hero.health -= 20;
				hero.healthBar.updateHealth(hero.health);
				if (hero.health <= 0) {
					LK.showGameOver();
				}
				enemies[i].destroy();
				enemies.splice(i, 1);
				continue;
			}
			if (enemies[i].y > 2732 + 50) {
				enemies[i].destroy();
				enemies.splice(i, 1);
				scoreTxt.setText(score);
			}
		}
		for (var i = 0; i < heroBullets.length; i++) {
			heroBullets[i].move();
			for (var j = 0; j < enemyBullets.length; j++) {
				if (heroBullets[i].intersects(enemyBullets[j])) {
					heroBullets[i].destroy();
					enemyBullets[j].destroy();
					heroBullets.splice(i, 1);
					enemyBullets.splice(j, 1);
					i--;
					break;
				}
			}
			for (var j = 0; j < enemies.length; j++) {
				if (heroBullets[i] && heroBullets[i].intersects(enemies[j])) {
					var explosion = new Explosion();
					explosion.x = enemies[j].x;
					explosion.y = enemies[j].y;
					self.addChild(explosion);
					enemies[j].destroy();
					if (Math.random() < 0.05) {
						var pickup = new HealthPickup();
						pickup.x = enemies[j].x;
						pickup.y = enemies[j].y - pickup.height;
						self.addChild(pickup);
					}
					enemies.splice(j, 1);
					score += 10;
					scoreTxt.setText(score);
					heroBullets[i].destroy();
					heroBullets.splice(i, 1);
					i--;
					break;
				}
			}
			if (heroBullets[i] && heroBullets[i].y < -50) {
				heroBullets[i].destroy();
				heroBullets.splice(i, 1);
			}
		}
		for (var i = 0; i < enemyBullets.length; i++) {
			enemyBullets[i].move();
			if (hero.intersects(enemyBullets[i])) {
				hero.health -= 20;
				hero.healthBar.updateHealth(hero.health);
				if (hero.health <= 0) {
					LK.showGameOver();
				}
				enemyBullets[i].destroy();
				enemyBullets.splice(i, 1);
				continue;
			}
			if (enemyBullets[i].y > 2732 + 50) {
				enemyBullets[i].destroy();
				enemyBullets.splice(i, 1);
			}
		}
	});
	hero.canShoot = true;
	hero.shootCooldown = 12;
	hero.lastShotTime = 0;
	hero.on('down', function (obj) {
		if (hero.canShoot) {
			var bullet = new HeroBullet();
			bullet.x = hero.x;
			bullet.y = hero.y;
			heroBullets.push(bullet);
			self.addChild(bullet);
			hero.canShoot = false;
			hero.lastShotTime = LK.ticks;
		}
	});
	LK.on('tick', function () {
		if (!hero.canShoot && LK.ticks - hero.lastShotTime > hero.shootCooldown) {
			hero.canShoot = true;
		}
	});
	var startTime = Date.now();
	var enemySpawnInterval = 2000;
	var maxEnemies = 5;
	var enemySpeedIncreaseTimer = LK.setInterval(function () {
		Enemy.prototype.baseSpeed *= 1.05;
		EnemyBullet.prototype.baseSpeed *= 1.05;
	}, 30000);
	var enemySpawnTimer = LK.setInterval(function () {
		var currentTime = Date.now();
		var elapsedTime = (currentTime - startTime) / 60000;
		maxEnemies = 5 + Math.floor(elapsedTime);
		if (enemies.length < maxEnemies) {
			var enemy = new Enemy();
			var enemyWidth = enemy.width;
			enemy.x = Math.random() * (2048 - enemyWidth) + enemyWidth / 2;
			enemy.y = -50;
			enemies.push(enemy);
			self.addChild(enemy);
		}
	}, enemySpawnInterval);
	LK.setInterval(function () {
		if (Math.random() < 0.1) {
			var pickup = new HealthPickup();
			pickup.x = Math.random() * (2048 - pickup.width) + pickup.width / 2;
			pickup.y = -50;
			self.addChild(pickup);
		} else {
			var enemyIndex = Math.floor(Math.random() * enemies.length);
			var bullet = new EnemyBullet();
			bullet.x = enemies[enemyIndex].x;
			bullet.y = enemies[enemyIndex].y;
			enemyBullets.push(bullet);
			self.addChild(bullet);
		}
	}, 2000);
});

===================================================================
--- original.js
+++ change.js
@@ -20,9 +20,9 @@
 	});
 	self.move = function () {
 		self.layers.forEach(function (layer) {
 			layer.y += layer.speed;
-			if (layer.y >= 2732) {
+			if (layer.y >= 2732 + 1000) {
 				layer.y -= 2732 * 2;
 			}
 			layer.x = 2048 - layer.width + 1000;
 		});
@@ -59,11 +59,11 @@
 var Hero = Container.expand(function () {
 	var self = Container.call(this);
 	var heroGraphics = self.createAsset('hero', 'Hero character', .5, .5);
 	self.healthBar = new HealthBar(100);
-	self.healthBar.x = 2048 / 2;
-	self.healthBar.y = 2732 - self.healthBar.height / 2;
-	self.addChild(self.healthBar);
+	self.healthBar.x = 10;
+	self.healthBar.y = 10;
+	LK.gui.topLeft.addChild(self.healthBar);
 	self.speed = 5;
 	self.health = 100;
 	self.healthBar.setMaxHealth(self.health);
 	self.healthBar.updateHealth(self.health);