/**** 
* Initialize Game
****/ 
/**** Initialize Game ****/
var game = new LK.Game({
	backgroundColor: 0x70c5ce
});

/**** 
* Game Code
****/ 
/**** Background ****/
var bg = LK.getAsset('background', {
	x: 0,
	y: 0
});
game.addChild(bg);
var ground = LK.getAsset('ground', {
	x: 0,
	y: 2532
});
game.addChild(ground);
var groundDirt = LK.getAsset('groundDirt', {
	x: 0,
	y: 2672
});
game.addChild(groundDirt);
/**** Bird ****/
var bird = new Container();
bird.attachAsset('bird', {
	anchorX: 0.5,
	anchorY: 0.5
});
bird.x = 400;
bird.y = 800;
game.addChild(bird);
var velocity = 0;
var gravity = 0.8;
var jump = -15;
var maxFall = 20;
/**** Pipes ****/
var pipes = [];
var pipeGap = 400;
var pipeSpeed = 10;
/**** Score ****/
var score = 0;
var scoreTxt = new Text2('0', {
	size: 150,
	fill: 0xFFFFFF
});
scoreTxt.anchor.set(1, 0);
scoreTxt.x = 1950;
scoreTxt.y = 50;
LK.gui.top.addChild(scoreTxt);
/**** Game Over Text ****/
var gameOverTxt = new Text2('GAME OVER', {
	size: 120,
	fill: 0xff0000
});
gameOverTxt.anchor.set(0.5);
gameOverTxt.x = 1024;
gameOverTxt.y = 900;
gameOverTxt.visible = false;
LK.gui.center.addChild(gameOverTxt);
/**** Restart Button ****/
var restartButton = LK.getAsset('restartButton', {
	anchorX: 0.5,
	anchorY: 0.5,
	x: 1024,
	y: 1300
});
restartButton.visible = false;
restartButton.interactive = true;
restartButton.on('pointerdown', resetGame);
LK.gui.center.addChild(restartButton);
/**** Spawn Pipes ****/
function spawnPipes() {
	var gapY = 500 + Math.random() * 1000;
	var topPipe = new Container();
	topPipe.attachAsset('pipe', {
		anchorX: 0.5,
		anchorY: 1
	});
	topPipe.x = 2200;
	topPipe.y = gapY - pipeGap / 2;
	var bottomPipe = new Container();
	bottomPipe.attachAsset('pipe', {
		anchorX: 0.5,
		anchorY: 0
	});
	bottomPipe.x = 2200;
	bottomPipe.y = gapY + pipeGap / 2;
	topPipe.passed = false;
	game.addChild(topPipe);
	game.addChild(bottomPipe);
	pipes.push({
		top: topPipe,
		bottom: bottomPipe
	});
}
/**** Collision ****/
function hitTest(bird, pipe) {
	return bird.x + 50 > pipe.x - pipe.width / 2 && bird.x - 50 < pipe.x + pipe.width / 2 && bird.y + 40 > pipe.y - pipe.height * pipe.anchorY && bird.y - 40 < pipe.y + pipe.height * (1 - pipe.anchorY);
}
/**** Controls ****/
game.down = function () {
	if (gameOver) return;
	velocity = jump;
};
/**** Game Loop ****/
var frame = 0;
var gameOver = false;
game.update = function () {
	if (gameOver) return;
	// Gravity
	velocity += gravity;
	if (velocity > maxFall) velocity = maxFall;
	bird.y += velocity;
	// Rotation
	bird.rotation = velocity * 0.05;
	// Ground & ceiling
	if (bird.y > 2600) {
		bird.y = 2600;
		endGame();
		return;
	}
	if (bird.y < 0) {
		bird.y = 0;
		velocity = 0;
	}
	// Spawn pipes
	frame++;
	if (frame % 90 === 0) {
		spawnPipes();
	}
	// Difficulty scaling
	if (score > 5) pipeSpeed = 12;
	if (score > 10) pipeSpeed = 14;
	if (score > 20) pipeSpeed = 16;
	// Move pipes
	for (var i = pipes.length - 1; i >= 0; i--) {
		var p = pipes[i];
		p.top.x -= pipeSpeed;
		p.bottom.x -= pipeSpeed;
		// Score
		if (!p.top.passed && p.top.x < bird.x) {
			p.top.passed = true;
			score++;
			scoreTxt.setText(score);
			LK.getSound('score').play();
		}
		// Collision
		if (hitTest(bird, p.top) || hitTest(bird, p.bottom)) {
			endGame();
			return;
		}
		// Remove pipes
		if (p.top.x < -200) {
			p.top.destroy();
			p.bottom.destroy();
			pipes.splice(i, 1);
		}
	}
};
/**** End Game ****/
function endGame() {
	if (gameOver) return;
	gameOver = true;
	velocity = 0;
	LK.getSound('hit').play();
	restartButton.visible = true;
	gameOverTxt.visible = true;
}
/**** Reset Game ****/
function resetGame() {
	gameOver = false;
	score = 0;
	scoreTxt.setText(score);
	velocity = 0;
	bird.y = 800;
	bird.rotation = 0;
	pipeSpeed = 10;
	// Clear pipes
	for (var i = pipes.length - 1; i >= 0; i--) {
		pipes[i].top.destroy();
		pipes[i].bottom.destroy();
	}
	pipes = [];
	frame = 0;
	restartButton.visible = false;
	gameOverTxt.visible = false;
}

===================================================================
--- original.js
+++ change.js
@@ -103,11 +103,10 @@
 	return bird.x + 50 > pipe.x - pipe.width / 2 && bird.x - 50 < pipe.x + pipe.width / 2 && bird.y + 40 > pipe.y - pipe.height * pipe.anchorY && bird.y - 40 < pipe.y + pipe.height * (1 - pipe.anchorY);
 }
 /**** Controls ****/
 game.down = function () {
-	if (!gameOver) {
-		velocity = jump;
-	}
+	if (gameOver) return;
+	velocity = jump;
 };
 /**** Game Loop ****/
 var frame = 0;
 var gameOver = false;
@@ -118,13 +117,18 @@
 	if (velocity > maxFall) velocity = maxFall;
 	bird.y += velocity;
 	// Rotation
 	bird.rotation = velocity * 0.05;
-	// Ground hit
-	if (bird.y > 2600 || bird.y < 0) {
+	// Ground & ceiling
+	if (bird.y > 2600) {
+		bird.y = 2600;
 		endGame();
 		return;
 	}
+	if (bird.y < 0) {
+		bird.y = 0;
+		velocity = 0;
+	}
 	// Spawn pipes
 	frame++;
 	if (frame % 90 === 0) {
 		spawnPipes();
@@ -159,9 +163,11 @@
 	}
 };
 /**** End Game ****/
 function endGame() {
+	if (gameOver) return;
 	gameOver = true;
+	velocity = 0;
 	LK.getSound('hit').play();
 	restartButton.visible = true;
 	gameOverTxt.visible = true;
 }
@@ -171,15 +177,16 @@
 	score = 0;
 	scoreTxt.setText(score);
 	velocity = 0;
 	bird.y = 800;
-	pipeSpeed = 10; // reset difficulty
+	bird.rotation = 0;
+	pipeSpeed = 10;
 	// Clear pipes
 	for (var i = pipes.length - 1; i >= 0; i--) {
 		pipes[i].top.destroy();
 		pipes[i].bottom.destroy();
-		pipes.splice(i, 1);
 	}
+	pipes = [];
 	frame = 0;
 	restartButton.visible = false;
 	gameOverTxt.visible = false;
 }
\ No newline at end of file