/**** 
* Classes
****/ 
//<Assets used in the game will automatically appear here>
//<Write imports for supported plugins here>
// Car class representing the player's vehicle
var Car = Container.expand(function () {
	var self = Container.call(this);
	var carGraphics = self.attachAsset('car', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = 10;
	self.update = function () {
		if (mouseDown) {
			// Increase the car's y position up to the center of the screen
			if (self.y > 2732 / 2) {
				self.y -= self.speed;
			}
			self.speed = 20;
		} else {
			// Revert the car's y position back to original when mouse button is not held
			if (self.y < 2400) {
				self.y += self.speed;
			}
			self.speed = 10;
		}
	};
});
// Obstacle class representing obstacles on the track
var Obstacle = Container.expand(function () {
	var self = Container.call(this);
	var obstacleGraphics = self.attachAsset('obstacle', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = 5;
	self.update = function () {
		self.y += self.speed;
		if (self.y > 2732) {
			self.y = -100; // Reset position to top
		}
	};
});
// Rival class representing rival cars
var Rival = Container.expand(function () {
	var self = Container.call(this);
	var rivalGraphics = self.attachAsset('rival', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = 8;
	self.update = function () {
		self.y += self.speed;
		if (self.y > 2732) {
			self.y = -100; // Reset position to top
		}
	};
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x000000 //Init game with black background 
});

/**** 
* Game Code
****/ 
// Initialize player car
var playerCar = game.addChild(new Car());
playerCar.x = 1024; // Center horizontally
playerCar.y = 2400; // Near the bottom
// Initialize obstacles
var obstacles = [];
for (var i = 0; i < 5; i++) {
	var obstacle = new Obstacle();
	obstacle.x = Math.random() * 2048;
	obstacle.y = Math.random() * -2732;
	obstacles.push(obstacle);
	game.addChild(obstacle);
}
// Initialize rivals
var rivals = [];
for (var i = 0; i < 3; i++) {
	var rival = new Rival();
	rival.x = Math.random() * 2048;
	rival.y = Math.random() * -2732;
	rivals.push(rival);
	game.addChild(rival);
}
// Handle player car movement
var mouseDown = false;
game.move = function (x, y, obj) {
	playerCar.x = x;
};
game.down = function (x, y, obj) {
	mouseDown = true;
};
game.up = function (x, y, obj) {
	mouseDown = false;
};
// Update game logic
game.update = function () {
	// Update obstacles
	for (var i = 0; i < obstacles.length; i++) {
		if (mouseDown) {
			obstacles[i].speed = 10;
		} else {
			obstacles[i].speed = 5;
		}
		obstacles[i].update();
		if (playerCar.intersects(obstacles[i])) {
			LK.effects.flashScreen(0xff0000, 1000);
			LK.showGameOver();
		}
	}
	// Update rivals
	for (var i = 0; i < rivals.length; i++) {
		if (mouseDown) {
			rivals[i].speed = 16;
		} else {
			rivals[i].speed = 8;
		}
		rivals[i].update();
		if (playerCar.intersects(rivals[i])) {
			LK.effects.flashScreen(0xff0000, 1000);
			LK.showGameOver();
		}
	}
};

===================================================================
--- original.js
+++ change.js
@@ -18,8 +18,12 @@
 				self.y -= self.speed;
 			}
 			self.speed = 20;
 		} else {
+			// Revert the car's y position back to original when mouse button is not held
+			if (self.y < 2400) {
+				self.y += self.speed;
+			}
 			self.speed = 10;
 		}
 	};
 });