===================================================================
--- original.js
+++ change.js
@@ -1,6 +1,305 @@
-/****
+/**** 
+* Plugins
+****/ 
+var tween = LK.import("@upit/tween.v1");
+
+/**** 
+* Classes
+****/ 
+var Bullet = Container.expand(function () {
+	var self = Container.call(this);
+	var bulletGraphics = self.attachAsset('bullet', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	self.speed = 8;
+	self.direction = {
+		x: 0,
+		y: -1
+	};
+	self.update = function () {
+		self.x += self.direction.x * self.speed;
+		self.y += self.direction.y * self.speed;
+	};
+	return self;
+});
+var HealthPack = Container.expand(function () {
+	var self = Container.call(this);
+	var healthGraphics = self.attachAsset('healthPack', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	self.healAmount = 25;
+	return self;
+});
+var Player = Container.expand(function () {
+	var self = Container.call(this);
+	var playerGraphics = self.attachAsset('player', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	self.health = 100;
+	self.maxHealth = 100;
+	self.lastShotTime = 0;
+	self.shootCooldown = 200; // milliseconds
+	self.facing = {
+		x: 0,
+		y: -1
+	}; // initially facing up
+	return self;
+});
+var WeaponUpgrade = Container.expand(function () {
+	var self = Container.call(this);
+	var weaponGraphics = self.attachAsset('weaponUpgrade', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	return self;
+});
+var Zombie = Container.expand(function () {
+	var self = Container.call(this);
+	var zombieGraphics = self.attachAsset('zombie', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	self.speed = 1;
+	self.health = 1;
+	self.update = function () {
+		if (player) {
+			var dx = player.x - self.x;
+			var dy = player.y - self.y;
+			var distance = Math.sqrt(dx * dx + dy * dy);
+			if (distance > 0) {
+				self.x += dx / distance * self.speed;
+				self.y += dy / distance * self.speed;
+			}
+		}
+	};
+	return self;
+});
+
+/**** 
 * Initialize Game
-****/
+****/ 
 var game = new LK.Game({
-	backgroundColor: 0x000000
-});
\ No newline at end of file
+	backgroundColor: 0x2d2d2d
+});
+
+/**** 
+* Game Code
+****/ 
+var player = null;
+var zombies = [];
+var bullets = [];
+var healthPacks = [];
+var weaponUpgrades = [];
+var gameTime = 0;
+var zombieSpawnRate = 120; // frames between spawns
+var lastZombieSpawn = 0;
+var lastPickupSpawn = 0;
+var pickupSpawnRate = 300; // frames between pickups
+var dragNode = null;
+var lastPlayerPosition = {
+	x: 0,
+	y: 0
+};
+// UI Elements
+var healthBar = LK.getAsset('healthPack', {
+	anchorX: 0,
+	anchorY: 0,
+	scaleX: 5,
+	scaleY: 0.5
+});
+var scoreTxt = new Text2('Score: 0', {
+	size: 60,
+	fill: 0xFFFFFF
+});
+scoreTxt.anchor.set(0.5, 0);
+var healthTxt = new Text2('Health: 100', {
+	size: 50,
+	fill: 0xFFFFFF
+});
+healthTxt.anchor.set(0, 0);
+LK.gui.top.addChild(scoreTxt);
+LK.gui.topRight.addChild(healthTxt);
+LK.gui.topRight.addChild(healthBar);
+healthBar.x = -200;
+healthBar.y = 60;
+// Initialize player
+player = game.addChild(new Player());
+player.x = 2048 / 2;
+player.y = 2732 / 2;
+lastPlayerPosition.x = player.x;
+lastPlayerPosition.y = player.y;
+function spawnZombie() {
+	var zombie = new Zombie();
+	var side = Math.floor(Math.random() * 4);
+	// Spawn from edges
+	switch (side) {
+		case 0:
+			// top
+			zombie.x = Math.random() * 2048;
+			zombie.y = -30;
+			break;
+		case 1:
+			// right
+			zombie.x = 2048 + 30;
+			zombie.y = Math.random() * 2732;
+			break;
+		case 2:
+			// bottom
+			zombie.x = Math.random() * 2048;
+			zombie.y = 2732 + 30;
+			break;
+		case 3:
+			// left
+			zombie.x = -30;
+			zombie.y = Math.random() * 2732;
+			break;
+	}
+	// Increase speed over time
+	zombie.speed = 1 + gameTime / 3600 * 0.5;
+	zombies.push(zombie);
+	game.addChild(zombie);
+}
+function spawnHealthPack() {
+	var healthPack = new HealthPack();
+	healthPack.x = Math.random() * (2048 - 100) + 50;
+	healthPack.y = Math.random() * (2732 - 100) + 50;
+	healthPacks.push(healthPack);
+	game.addChild(healthPack);
+}
+function spawnWeaponUpgrade() {
+	var weaponUpgrade = new WeaponUpgrade();
+	weaponUpgrade.x = Math.random() * (2048 - 100) + 50;
+	weaponUpgrade.y = Math.random() * (2732 - 100) + 50;
+	weaponUpgrades.push(weaponUpgrade);
+	game.addChild(weaponUpgrade);
+}
+function shootBullet() {
+	if (Date.now() - player.lastShotTime > player.shootCooldown) {
+		var bullet = new Bullet();
+		bullet.x = player.x;
+		bullet.y = player.y;
+		bullet.direction.x = player.facing.x;
+		bullet.direction.y = player.facing.y;
+		bullets.push(bullet);
+		game.addChild(bullet);
+		player.lastShotTime = Date.now();
+		LK.getSound('shoot').play();
+	}
+}
+function updatePlayerFacing() {
+	var dx = player.x - lastPlayerPosition.x;
+	var dy = player.y - lastPlayerPosition.y;
+	var distance = Math.sqrt(dx * dx + dy * dy);
+	if (distance > 2) {
+		player.facing.x = dx / distance;
+		player.facing.y = dy / distance;
+	}
+	lastPlayerPosition.x = player.x;
+	lastPlayerPosition.y = player.y;
+}
+game.down = function (x, y, obj) {
+	dragNode = player;
+	player.x = x;
+	player.y = y;
+};
+game.move = function (x, y, obj) {
+	if (dragNode) {
+		dragNode.x = x;
+		dragNode.y = y;
+	}
+};
+game.up = function (x, y, obj) {
+	dragNode = null;
+};
+game.update = function () {
+	gameTime++;
+	// Update player facing direction
+	updatePlayerFacing();
+	// Auto shoot
+	shootBullet();
+	// Spawn zombies
+	if (gameTime - lastZombieSpawn > zombieSpawnRate) {
+		spawnZombie();
+		lastZombieSpawn = gameTime;
+		// Increase spawn rate over time
+		zombieSpawnRate = Math.max(30, 120 - Math.floor(gameTime / 600));
+	}
+	// Spawn pickups
+	if (gameTime - lastPickupSpawn > pickupSpawnRate) {
+		if (Math.random() > 0.5) {
+			spawnHealthPack();
+		} else {
+			spawnWeaponUpgrade();
+		}
+		lastPickupSpawn = gameTime;
+	}
+	// Update bullets
+	for (var i = bullets.length - 1; i >= 0; i--) {
+		var bullet = bullets[i];
+		// Remove off-screen bullets
+		if (bullet.x < -50 || bullet.x > 2098 || bullet.y < -50 || bullet.y > 2782) {
+			bullet.destroy();
+			bullets.splice(i, 1);
+			continue;
+		}
+		// Check bullet-zombie collisions
+		for (var j = zombies.length - 1; j >= 0; j--) {
+			var zombie = zombies[j];
+			if (bullet.intersects(zombie)) {
+				LK.setScore(LK.getScore() + 10);
+				scoreTxt.setText('Score: ' + LK.getScore());
+				LK.getSound('zombieHit').play();
+				bullet.destroy();
+				bullets.splice(i, 1);
+				zombie.destroy();
+				zombies.splice(j, 1);
+				break;
+			}
+		}
+	}
+	// Update zombies and check player collision
+	for (var i = zombies.length - 1; i >= 0; i--) {
+		var zombie = zombies[i];
+		if (zombie.intersects(player)) {
+			player.health -= 2;
+			LK.getSound('damage').play();
+			LK.effects.flashObject(player, 0xff0000, 200);
+			if (player.health <= 0) {
+				LK.showGameOver();
+				return;
+			}
+			healthTxt.setText('Health: ' + player.health);
+			healthBar.scaleX = player.health / player.maxHealth * 5;
+		}
+	}
+	// Check health pack collection
+	for (var i = healthPacks.length - 1; i >= 0; i--) {
+		var healthPack = healthPacks[i];
+		if (player.intersects(healthPack)) {
+			player.health = Math.min(player.maxHealth, player.health + healthPack.healAmount);
+			healthTxt.setText('Health: ' + player.health);
+			healthBar.scaleX = player.health / player.maxHealth * 5;
+			LK.getSound('pickup').play();
+			healthPack.destroy();
+			healthPacks.splice(i, 1);
+		}
+	}
+	// Check weapon upgrade collection
+	for (var i = weaponUpgrades.length - 1; i >= 0; i--) {
+		var weaponUpgrade = weaponUpgrades[i];
+		if (player.intersects(weaponUpgrade)) {
+			player.shootCooldown = Math.max(50, player.shootCooldown - 20);
+			LK.getSound('pickup').play();
+			weaponUpgrade.destroy();
+			weaponUpgrades.splice(i, 1);
+		}
+	}
+	// Increase score over time
+	if (gameTime % 60 === 0) {
+		LK.setScore(LK.getScore() + 1);
+		scoreTxt.setText('Score: ' + LK.getScore());
+	}
+};
\ No newline at end of file