/**** 
* Plugins
****/ 
var tween = LK.import("@upit/tween.v1");

/**** 
* Classes
****/ 
var Bird = Container.expand(function () {
	var self = Container.call(this);
	var birdGraphics = self.attachAsset('bird', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.velocity = 0;
	self.gravity = 0.8;
	self.jumpStrength = -12;
	self.flap = function () {
		self.velocity = self.jumpStrength;
		LK.getSound('flap').play();
	};
	self.update = function () {
		if (!gameStarted) {
			// Don't apply physics before game starts
			return;
		}
		self.velocity += self.gravity;
		self.y += self.velocity;
		// Rotate bird based on velocity
		birdGraphics.rotation = Math.max(-0.5, Math.min(1.5, self.velocity * 0.1));
		// Limit bird movement to screen bounds
		if (self.y < 30) {
			self.y = 30;
		}
	};
	return self;
});
var Pipe = Container.expand(function (gapCenterY) {
	var self = Container.call(this);
	self.gapSize = 400;
	self.speed = -3;
	self.passed = false;
	self.gapCenterY = gapCenterY;
	// Create top pipe
	var topPipe = self.attachAsset('pipe', {
		anchorX: 0.5,
		anchorY: 1
	});
	topPipe.y = gapCenterY - self.gapSize / 2;
	topPipe.height = gapCenterY - self.gapSize / 2;
	// Create bottom pipe
	var bottomPipe = self.attachAsset('pipe', {
		anchorX: 0.5,
		anchorY: 0
	});
	bottomPipe.y = gapCenterY + self.gapSize / 2;
	bottomPipe.height = 2732 - 150 - (gapCenterY + self.gapSize / 2);
	self.update = function () {
		self.x += self.speed;
	};
	return self;
});

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

/**** 
* Game Code
****/ 
// Game variables
var bird;
var pipes = [];
var ground;
var gameStarted = false;
var gameOver = false;
var pipeSpacing = 400;
var nextPipeX = 2048;
// Create score display
var scoreTxt = new Text2('SKOR: 0', {
	size: 80,
	fill: 0xFFFFFF
});
scoreTxt.anchor.set(0.5, 0);
scoreTxt.stroke = 0x000000;
scoreTxt.strokeThickness = 4;
LK.gui.top.addChild(scoreTxt);
scoreTxt.y = 100;
// Create instruction text
var instructionTxt = new Text2('TIKLA VE OYNA!', {
	size: 60,
	fill: 0xFFFFFF
});
instructionTxt.anchor.set(0.5, 0.5);
instructionTxt.stroke = 0x000000;
instructionTxt.strokeThickness = 3;
LK.gui.center.addChild(instructionTxt);
// Create bird
bird = game.addChild(new Bird());
bird.x = 400;
bird.y = 1366;
// Create invisible barrier blocks to constrain bird before game starts
var topBarrier = game.addChild(LK.getAsset('barrier', {
	anchorX: 0.5,
	anchorY: 1
}));
topBarrier.x = 400;
topBarrier.y = 1316; // 50 pixels above bird
topBarrier.alpha = 0; // Make invisible
var bottomBarrier = game.addChild(LK.getAsset('barrier', {
	anchorX: 0.5,
	anchorY: 0
}));
bottomBarrier.x = 400;
bottomBarrier.y = 1416; // 50 pixels below bird
bottomBarrier.alpha = 0; // Make invisible
// Create ground
ground = game.addChild(LK.getAsset('ground', {
	anchorX: 0,
	anchorY: 1
}));
ground.x = 0;
ground.y = 2732;
// Create pipe function
function createPipe() {
	var minGapY = 400;
	var maxGapY = 2182; // 2732 - 150 - 400
	var gapCenterY = minGapY + Math.random() * (maxGapY - minGapY);
	var pipe = new Pipe(gapCenterY);
	pipe.x = nextPipeX;
	pipes.push(pipe);
	game.addChild(pipe);
	nextPipeX += pipeSpacing;
}
// Reset game function
function resetGame() {
	// Reset bird
	bird.x = 400;
	bird.y = 1366;
	bird.velocity = 0;
	// Clear pipes
	for (var i = pipes.length - 1; i >= 0; i--) {
		pipes[i].destroy();
	}
	pipes = [];
	// Reset variables
	nextPipeX = 2048;
	gameStarted = false;
	gameOver = false;
	LK.setScore(0);
	scoreTxt.setText('SKOR: 0');
	// Show instruction
	instructionTxt.visible = true;
	// Recreate invisible barriers
	topBarrier = game.addChild(LK.getAsset('barrier', {
		anchorX: 0.5,
		anchorY: 1
	}));
	topBarrier.x = 400;
	topBarrier.y = 1316; // 50 pixels above bird
	topBarrier.alpha = 0; // Make invisible
	bottomBarrier = game.addChild(LK.getAsset('barrier', {
		anchorX: 0.5,
		anchorY: 0
	}));
	bottomBarrier.x = 400;
	bottomBarrier.y = 1416; // 50 pixels below bird
	bottomBarrier.alpha = 0; // Make invisible
	// Create initial pipes
	createPipe();
	createPipe();
}
// Initialize game
createPipe();
createPipe();
// Touch/click handler
game.down = function (x, y, obj) {
	if (gameOver) {
		resetGame();
		return;
	}
	if (!gameStarted) {
		gameStarted = true;
		instructionTxt.visible = false;
		// Remove invisible barriers when game starts
		if (topBarrier) {
			topBarrier.destroy();
			topBarrier = null;
		}
		if (bottomBarrier) {
			bottomBarrier.destroy();
			bottomBarrier = null;
		}
	}
	bird.flap();
};
// Main game loop
game.update = function () {
	if (!gameStarted || gameOver) return;
	// Check ground collision
	if (bird.y + 20 >= 2732 - 150) {
		gameOver = true;
		LK.showGameOver();
		return;
	}
	// Check ceiling collision
	if (bird.y - 20 <= 0) {
		gameOver = true;
		LK.showGameOver();
		return;
	}
	// Check pipe collisions and scoring
	for (var i = 0; i < pipes.length; i++) {
		var pipe = pipes[i];
		// Check if bird is within pipe horizontally
		if (bird.x + 30 > pipe.x - 50 && bird.x - 30 < pipe.x + 50) {
			// Check collision with top pipe
			if (bird.y - 20 < pipe.gapCenterY - pipe.gapSize / 2) {
				gameOver = true;
				LK.showGameOver();
				return;
			}
			// Check collision with bottom pipe
			if (bird.y + 20 > pipe.gapCenterY + pipe.gapSize / 2) {
				gameOver = true;
				LK.showGameOver();
				return;
			}
		}
		// Check scoring
		if (!pipe.passed && pipe.x + 50 < bird.x) {
			pipe.passed = true;
			LK.setScore(LK.getScore() + 1);
			scoreTxt.setText('SKOR: ' + LK.getScore());
			LK.getSound('score').play();
		}
	}
	// Create new pipes
	if (pipes.length === 0 || nextPipeX - pipes[pipes.length - 1].x >= pipeSpacing) {
		createPipe();
	}
	// Remove off-screen pipes
	for (var j = pipes.length - 1; j >= 0; j--) {
		if (pipes[j].x < -100) {
			pipes[j].destroy();
			pipes.splice(j, 1);
		}
	}
};

===================================================================
--- original.js
+++ change.js
@@ -19,8 +19,12 @@
 		self.velocity = self.jumpStrength;
 		LK.getSound('flap').play();
 	};
 	self.update = function () {
+		if (!gameStarted) {
+			// Don't apply physics before game starts
+			return;
+		}
 		self.velocity += self.gravity;
 		self.y += self.velocity;
 		// Rotate bird based on velocity
 		birdGraphics.rotation = Math.max(-0.5, Math.min(1.5, self.velocity * 0.1));
@@ -97,8 +101,23 @@
 // Create bird
 bird = game.addChild(new Bird());
 bird.x = 400;
 bird.y = 1366;
+// Create invisible barrier blocks to constrain bird before game starts
+var topBarrier = game.addChild(LK.getAsset('barrier', {
+	anchorX: 0.5,
+	anchorY: 1
+}));
+topBarrier.x = 400;
+topBarrier.y = 1316; // 50 pixels above bird
+topBarrier.alpha = 0; // Make invisible
+var bottomBarrier = game.addChild(LK.getAsset('barrier', {
+	anchorX: 0.5,
+	anchorY: 0
+}));
+bottomBarrier.x = 400;
+bottomBarrier.y = 1416; // 50 pixels below bird
+bottomBarrier.alpha = 0; // Make invisible
 // Create ground
 ground = game.addChild(LK.getAsset('ground', {
 	anchorX: 0,
 	anchorY: 1
@@ -134,8 +153,23 @@
 	LK.setScore(0);
 	scoreTxt.setText('SKOR: 0');
 	// Show instruction
 	instructionTxt.visible = true;
+	// Recreate invisible barriers
+	topBarrier = game.addChild(LK.getAsset('barrier', {
+		anchorX: 0.5,
+		anchorY: 1
+	}));
+	topBarrier.x = 400;
+	topBarrier.y = 1316; // 50 pixels above bird
+	topBarrier.alpha = 0; // Make invisible
+	bottomBarrier = game.addChild(LK.getAsset('barrier', {
+		anchorX: 0.5,
+		anchorY: 0
+	}));
+	bottomBarrier.x = 400;
+	bottomBarrier.y = 1416; // 50 pixels below bird
+	bottomBarrier.alpha = 0; // Make invisible
 	// Create initial pipes
 	createPipe();
 	createPipe();
 }
@@ -150,8 +184,17 @@
 	}
 	if (!gameStarted) {
 		gameStarted = true;
 		instructionTxt.visible = false;
+		// Remove invisible barriers when game starts
+		if (topBarrier) {
+			topBarrier.destroy();
+			topBarrier = null;
+		}
+		if (bottomBarrier) {
+			bottomBarrier.destroy();
+			bottomBarrier = null;
+		}
 	}
 	bird.flap();
 };
 // Main game loop