/**** 
* Plugins
****/ 
var tween = LK.import("@upit/tween.v1");
var storage = LK.import("@upit/storage.v1", {
	maxPassUnlocked: 1
});

/**** 
* Classes
****/ 
var Bird = Container.expand(function () {
	var self = Container.call(this);
	var birdGraphics = self.attachAsset('bird', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.isFlipped = false;
	self.baseY = 1366; // Middle of screen (2732 / 2)
	self.flippedY = 683; // Upper third
	self.velocity = 0;
	self.gravity = 0.4;
	self.maxVelocity = 15;
	self.flip = function () {
		self.isFlipped = !self.isFlipped;
		var targetY = self.isFlipped ? self.flippedY : self.baseY;
		tween(self, {
			y: targetY
		}, {
			duration: 200,
			easing: tween.easeInOut
		});
		LK.getSound('flip').play();
	};
	self.update = function () {
		if (!self.isFlipped) {
			self.velocity += self.gravity;
			if (self.velocity > self.maxVelocity) {
				self.velocity = self.maxVelocity;
			}
		} else {
			self.velocity -= self.gravity;
			if (self.velocity < -self.maxVelocity) {
				self.velocity = -self.maxVelocity;
			}
		}
		self.y += self.velocity;
		// Boundary check
		if (self.y < 30) {
			self.y = 30;
			self.velocity = 0;
		}
		if (self.y > 2702) {
			self.y = 2702;
			self.velocity = 0;
		}
	};
	return self;
});
var Obstacle = Container.expand(function () {
	var self = Container.call(this);
	self.speed = 8;
	self.gapSize = 300;
	self.gapPosition = 0; // 0 = top, 1 = middle, 2 = bottom
	var topPart = self.attachAsset('obstacle', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	var bottomPart = LK.getAsset('obstacle', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.addChild(bottomPart);
	self.setupObstacle = function (position) {
		self.gapPosition = position;
		var obstacleHeight = 200;
		var screenHeight = 2732;
		var gapSize = self.gapSize;
		var totalHeight = screenHeight - gapSize;
		if (position === 0) {
			// Gap at top
			topPart.y = -gapSize / 2 - obstacleHeight / 2;
			bottomPart.y = gapSize / 2 + obstacleHeight / 2;
		} else if (position === 1) {
			// Gap in middle
			topPart.y = -(gapSize / 2 + obstacleHeight / 2);
			bottomPart.y = gapSize / 2 + obstacleHeight / 2;
		} else {
			// Gap at bottom
			topPart.y = -gapSize / 2 - obstacleHeight / 2;
			bottomPart.y = screenHeight - gapSize / 2 + obstacleHeight / 2;
		}
	};
	self.update = function () {
		self.x -= self.speed;
	};
	return self;
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x87CEEB
});

/**** 
* Game Code
****/ 
var bird;
var obstacles = [];
var score = 0;
var gameActive = false;
var obstacleSpawnRate = 80;
var spawnCounter = 0;
var difficulty = 1;
var difficultyIncrement = 0.0002;
var scoreTxt;
var currentPass = 1;
var maxPassUnlocked = 1;
// Load saved pass data
maxPassUnlocked = storage.maxPassUnlocked || 1;
function initializeGame() {
	if (bird) {
		bird.destroy();
	}
	bird = game.addChild(new Bird());
	bird.x = 300;
	bird.y = bird.baseY;
	obstacles = [];
	score = 0;
	gameActive = true;
	spawnCounter = 0;
	difficulty = 1;
	obstacleSpawnRate = 80;
	if (!scoreTxt) {
		scoreTxt = new Text2('0', {
			size: 100,
			fill: 0x000000
		});
		scoreTxt.anchor.set(0.5, 0);
		LK.gui.top.addChild(scoreTxt);
	}
	updateScore();
	hideMainMenu();
}
function showMainMenu() {
	gameActive = false;
	LK.gui.center.removeChildren();
	var menuContainer = new Container();
	LK.gui.center.addChild(menuContainer);
	var titleTxt = new Text2('FLIPY BIRD YAP', {
		size: 80,
		fill: 0x000000
	});
	titleTxt.anchor.set(0.5, 0.5);
	titleTxt.y = -200;
	menuContainer.addChild(titleTxt);
	var passLabelTxt = new Text2('Pass: ' + currentPass + ' / ' + maxPassUnlocked, {
		size: 50,
		fill: 0x000000
	});
	passLabelTxt.anchor.set(0.5, 0.5);
	passLabelTxt.y = -50;
	menuContainer.addChild(passLabelTxt);
	var playButtonBg = LK.getAsset('gap', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	playButtonBg.tint = 0x4CAF50;
	playButtonBg.x = 0;
	playButtonBg.y = 80;
	playButtonBg.width = 300;
	playButtonBg.height = 100;
	menuContainer.addChild(playButtonBg);
	var playTxt = new Text2('PLAY', {
		size: 60,
		fill: 0xffffff
	});
	playTxt.anchor.set(0.5, 0.5);
	playTxt.x = 0;
	playTxt.y = 80;
	menuContainer.addChild(playTxt);
	playButtonBg.interactive = true;
	playButtonBg.down = function () {
		initializeGame();
	};
	if (currentPass > 1) {
		var prevButtonBg = LK.getAsset('gap', {
			anchorX: 0.5,
			anchorY: 0.5
		});
		prevButtonBg.tint = 0x2196F3;
		prevButtonBg.x = -180;
		prevButtonBg.y = 250;
		prevButtonBg.width = 120;
		prevButtonBg.height = 80;
		menuContainer.addChild(prevButtonBg);
		var prevTxt = new Text2('<', {
			size: 50,
			fill: 0xffffff
		});
		prevTxt.anchor.set(0.5, 0.5);
		prevTxt.x = -180;
		prevTxt.y = 250;
		menuContainer.addChild(prevTxt);
		prevButtonBg.interactive = true;
		prevButtonBg.down = function () {
			currentPass = Math.max(1, currentPass - 1);
			showMainMenu();
		};
	}
	if (currentPass < maxPassUnlocked) {
		var nextButtonBg = LK.getAsset('gap', {
			anchorX: 0.5,
			anchorY: 0.5
		});
		nextButtonBg.tint = 0x2196F3;
		nextButtonBg.x = 180;
		nextButtonBg.y = 250;
		nextButtonBg.width = 120;
		nextButtonBg.height = 80;
		menuContainer.addChild(nextButtonBg);
		var nextTxt = new Text2('>', {
			size: 50,
			fill: 0xffffff
		});
		nextTxt.anchor.set(0.5, 0.5);
		nextTxt.x = 180;
		nextTxt.y = 250;
		menuContainer.addChild(nextTxt);
		nextButtonBg.interactive = true;
		nextButtonBg.down = function () {
			currentPass = Math.min(maxPassUnlocked, currentPass + 1);
			showMainMenu();
		};
	}
}
function hideMainMenu() {
	LK.gui.center.removeChildren();
}
function updateScore() {
	scoreTxt.setText(score);
	LK.setScore(score);
}
function spawnObstacle() {
	var obstacle = game.addChild(new Obstacle());
	obstacle.x = 2048 + 200;
	obstacle.y = 1366;
	var positions = [0, 1, 2];
	var randomPosition = positions[Math.floor(Math.random() * positions.length)];
	obstacle.setupObstacle(randomPosition);
	obstacle.passed = false;
	obstacles.push(obstacle);
}
function endGame() {
	gameActive = false;
	LK.effects.flashScreen(0xFF0000, 500);
	LK.getSound('hit').play();
	LK.setTimeout(function () {
		LK.showGameOver();
	}, 500);
}
game.down = function (x, y, obj) {
	if (gameActive) {
		bird.flip();
	}
};
game.move = function (x, y, obj) {
	// Empty move handler required for touch compatibility
};
game.up = function (x, y, obj) {
	// Empty up handler
};
game.update = function () {
	if (!gameActive) {
		return;
	}
	// Update difficulty
	difficulty += difficultyIncrement;
	obstacleSpawnRate = Math.max(40, 80 - Math.floor(difficulty * 5));
	// Update bird
	bird.update();
	// Spawn obstacles
	spawnCounter++;
	if (spawnCounter >= obstacleSpawnRate) {
		spawnObstacle();
		spawnCounter = 0;
	}
	// Update obstacles
	for (var i = obstacles.length - 1; i >= 0; i--) {
		var obstacle = obstacles[i];
		obstacle.speed = 8 + difficulty * 0.5;
		obstacle.update();
		// Check if bird passed obstacle
		if (!obstacle.passed && bird.x > obstacle.x) {
			obstacle.passed = true;
			score++;
			updateScore();
			LK.getSound('score').play();
			// Win condition
			if (score >= 50) {
				gameActive = false;
				if (currentPass === maxPassUnlocked) {
					maxPassUnlocked++;
					storage.maxPassUnlocked = maxPassUnlocked;
				}
				LK.effects.flashScreen(0x00FF00, 500);
				LK.setTimeout(function () {
					LK.showYouWin();
				}, 500);
				return;
			}
		}
		// Check collision with bird
		var birdRadius = 30;
		var obstacleWidth = 80;
		var gapSize = obstacle.gapSize;
		var obstacleHeight = 200;
		var birdLeft = bird.x - birdRadius;
		var birdRight = bird.x + birdRadius;
		var birdTop = bird.y - birdRadius;
		var birdBottom = bird.y + birdRadius;
		var obstacleLeft = obstacle.x - obstacleWidth / 2;
		var obstacleRight = obstacle.x + obstacleWidth / 2;
		if (birdRight > obstacleLeft && birdLeft < obstacleRight) {
			// Check vertical collision
			var gapCenter = obstacle.y;
			var gapTop = gapCenter - gapSize / 2;
			var gapBottom = gapCenter + gapSize / 2;
			if (birdTop < gapTop || birdBottom > gapBottom) {
				endGame();
				return;
			}
		}
		// Remove off-screen obstacles
		if (obstacle.x < -200) {
			obstacle.destroy();
			obstacles.splice(i, 1);
		}
	}
	// Boundary collision
	if (bird.y - 30 <= 0 || bird.y + 30 >= 2732) {
		endGame();
		return;
	}
};
LK.playMusic('bgmusic', {
	loop: true
});
showMainMenu();

===================================================================
--- original.js
+++ change.js
@@ -1,9 +1,11 @@
 /**** 
 * Plugins
 ****/ 
 var tween = LK.import("@upit/tween.v1");
-var storage = LK.import("@upit/storage.v1");
+var storage = LK.import("@upit/storage.v1", {
+	maxPassUnlocked: 1
+});
 
 /**** 
 * Classes
 ****/ 
@@ -104,24 +106,140 @@
 
 /**** 
 * Game Code
 ****/ 
-var bird = game.addChild(new Bird());
-bird.x = 300;
-bird.y = bird.baseY;
+var bird;
 var obstacles = [];
 var score = 0;
-var gameActive = true;
+var gameActive = false;
 var obstacleSpawnRate = 80;
 var spawnCounter = 0;
 var difficulty = 1;
 var difficultyIncrement = 0.0002;
-var scoreTxt = new Text2('0', {
-	size: 100,
-	fill: 0x000000
-});
-scoreTxt.anchor.set(0.5, 0);
-LK.gui.top.addChild(scoreTxt);
+var scoreTxt;
+var currentPass = 1;
+var maxPassUnlocked = 1;
+// Load saved pass data
+maxPassUnlocked = storage.maxPassUnlocked || 1;
+function initializeGame() {
+	if (bird) {
+		bird.destroy();
+	}
+	bird = game.addChild(new Bird());
+	bird.x = 300;
+	bird.y = bird.baseY;
+	obstacles = [];
+	score = 0;
+	gameActive = true;
+	spawnCounter = 0;
+	difficulty = 1;
+	obstacleSpawnRate = 80;
+	if (!scoreTxt) {
+		scoreTxt = new Text2('0', {
+			size: 100,
+			fill: 0x000000
+		});
+		scoreTxt.anchor.set(0.5, 0);
+		LK.gui.top.addChild(scoreTxt);
+	}
+	updateScore();
+	hideMainMenu();
+}
+function showMainMenu() {
+	gameActive = false;
+	LK.gui.center.removeChildren();
+	var menuContainer = new Container();
+	LK.gui.center.addChild(menuContainer);
+	var titleTxt = new Text2('FLIPY BIRD YAP', {
+		size: 80,
+		fill: 0x000000
+	});
+	titleTxt.anchor.set(0.5, 0.5);
+	titleTxt.y = -200;
+	menuContainer.addChild(titleTxt);
+	var passLabelTxt = new Text2('Pass: ' + currentPass + ' / ' + maxPassUnlocked, {
+		size: 50,
+		fill: 0x000000
+	});
+	passLabelTxt.anchor.set(0.5, 0.5);
+	passLabelTxt.y = -50;
+	menuContainer.addChild(passLabelTxt);
+	var playButtonBg = LK.getAsset('gap', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	playButtonBg.tint = 0x4CAF50;
+	playButtonBg.x = 0;
+	playButtonBg.y = 80;
+	playButtonBg.width = 300;
+	playButtonBg.height = 100;
+	menuContainer.addChild(playButtonBg);
+	var playTxt = new Text2('PLAY', {
+		size: 60,
+		fill: 0xffffff
+	});
+	playTxt.anchor.set(0.5, 0.5);
+	playTxt.x = 0;
+	playTxt.y = 80;
+	menuContainer.addChild(playTxt);
+	playButtonBg.interactive = true;
+	playButtonBg.down = function () {
+		initializeGame();
+	};
+	if (currentPass > 1) {
+		var prevButtonBg = LK.getAsset('gap', {
+			anchorX: 0.5,
+			anchorY: 0.5
+		});
+		prevButtonBg.tint = 0x2196F3;
+		prevButtonBg.x = -180;
+		prevButtonBg.y = 250;
+		prevButtonBg.width = 120;
+		prevButtonBg.height = 80;
+		menuContainer.addChild(prevButtonBg);
+		var prevTxt = new Text2('<', {
+			size: 50,
+			fill: 0xffffff
+		});
+		prevTxt.anchor.set(0.5, 0.5);
+		prevTxt.x = -180;
+		prevTxt.y = 250;
+		menuContainer.addChild(prevTxt);
+		prevButtonBg.interactive = true;
+		prevButtonBg.down = function () {
+			currentPass = Math.max(1, currentPass - 1);
+			showMainMenu();
+		};
+	}
+	if (currentPass < maxPassUnlocked) {
+		var nextButtonBg = LK.getAsset('gap', {
+			anchorX: 0.5,
+			anchorY: 0.5
+		});
+		nextButtonBg.tint = 0x2196F3;
+		nextButtonBg.x = 180;
+		nextButtonBg.y = 250;
+		nextButtonBg.width = 120;
+		nextButtonBg.height = 80;
+		menuContainer.addChild(nextButtonBg);
+		var nextTxt = new Text2('>', {
+			size: 50,
+			fill: 0xffffff
+		});
+		nextTxt.anchor.set(0.5, 0.5);
+		nextTxt.x = 180;
+		nextTxt.y = 250;
+		menuContainer.addChild(nextTxt);
+		nextButtonBg.interactive = true;
+		nextButtonBg.down = function () {
+			currentPass = Math.min(maxPassUnlocked, currentPass + 1);
+			showMainMenu();
+		};
+	}
+}
+function hideMainMenu() {
+	LK.gui.center.removeChildren();
+}
 function updateScore() {
 	scoreTxt.setText(score);
 	LK.setScore(score);
 }
@@ -182,8 +300,12 @@
 			LK.getSound('score').play();
 			// Win condition
 			if (score >= 50) {
 				gameActive = false;
+				if (currentPass === maxPassUnlocked) {
+					maxPassUnlocked++;
+					storage.maxPassUnlocked = maxPassUnlocked;
+				}
 				LK.effects.flashScreen(0x00FF00, 500);
 				LK.setTimeout(function () {
 					LK.showYouWin();
 				}, 500);
@@ -224,5 +346,6 @@
 	}
 };
 LK.playMusic('bgmusic', {
 	loop: true
-});
\ No newline at end of file
+});
+showMainMenu();
\ No newline at end of file