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

/**** 
* Classes
****/ 
// Enemy Car Class
var EnemyCar = Container.expand(function () {
	var self = Container.call(this);
	var car = self.attachAsset('enemyCar', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.lane = 1;
	self.speed = 18;
	self.update = function () {
		self.y += self.speed * gameSpeed;
	};
	return self;
});
// Lane Divider Class
var LaneDivider = Container.expand(function () {
	var self = Container.call(this);
	var div = self.attachAsset('laneDivider', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = 18;
	self.update = function () {
		self.y += self.speed * gameSpeed;
	};
	return self;
});
// Obstacle Class
var Obstacle = Container.expand(function () {
	var self = Container.call(this);
	var obs = self.attachAsset('obstacle', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.lane = 1;
	self.speed = 18;
	self.update = function () {
		self.y += self.speed * gameSpeed;
	};
	return self;
});
// Player Car Class
var PlayerCar = Container.expand(function () {
	var self = Container.call(this);
	var car = self.attachAsset('playerCar', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.lane = 1; // 0: left, 1: center, 2: right
	self.setLane = function (laneIdx) {
		self.lane = laneIdx;
		// Animate to new lane position
		var targetX = lanes[self.lane];
		tween(self, {
			x: targetX
		}, {
			duration: 120,
			easing: tween.cubicOut
		});
	};
	return self;
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x222222
});

/**** 
* Game Code
****/ 
// Music (background)
// Sound for lane change
// Sound for crash
// Road lane divider
// Obstacle (barrier)
// Enemy car
// Car (player)
// Lane positions (3 lanes)
var laneCount = 3;
var laneWidth = 410;
var lanes = [2048 / 2 - laneWidth,
// left
2048 / 2,
// center
2048 / 2 + laneWidth // right
];
// Game variables
var playerCar;
var enemyCars = [];
var obstacles = [];
var laneDividers = [];
var score = 0;
var scoreTxt;
var gameSpeed = 1;
var ticksSinceStart = 0;
var swipeStartX = null;
var swipeStartY = null;
var swipeActive = false;
var lastLane = 1;
var spawnTick = 0;
var dividerSpacing = 320;
var dragNode = null;
// Score display
scoreTxt = new Text2('0', {
	size: 120,
	fill: "#fff"
});
scoreTxt.anchor.set(0.5, 0);
LK.gui.top.addChild(scoreTxt);
// Start music
LK.playMusic('bgmusic');
// Create player car
playerCar = new PlayerCar();
playerCar.x = lanes[1];
playerCar.y = 2732 - 500;
playerCar.setLane(1);
game.addChild(playerCar);
// Create lane dividers (vertical lines for each lane)
// Draw a divider for each lane boundary (between lanes)
for (var l = 0; l < laneCount + 1; l++) {
	// For 3 lanes, this will draw 4 lines: left edge, between lanes, right edge
	// But we want only the lines between lanes, so skip the first and last
	if (l === 0 || l === laneCount) continue;
	for (var i = 0; i < 10; i++) {
		var divider = new LaneDivider();
		// Place the divider at the correct X for the lane line
		divider.x = (lanes[l - 1] + lanes[l]) / 2;
		divider.y = i * dividerSpacing;
		laneDividers.push(divider);
		game.addChild(divider);
	}
}
// Helper: spawn enemy car or obstacle
function spawnObstacleOrEnemy() {
	// Randomly decide: 70% enemy car, 30% obstacle
	var isEnemy = Math.random() < 0.7;
	var laneIdx = Math.floor(Math.random() * laneCount);
	var y = -300;
	if (isEnemy) {
		var enemy = new EnemyCar();
		enemy.lane = laneIdx;
		enemy.x = lanes[laneIdx];
		enemy.y = y;
		enemyCars.push(enemy);
		game.addChild(enemy);
	} else {
		var obs = new Obstacle();
		obs.lane = laneIdx;
		obs.x = lanes[laneIdx];
		obs.y = y;
		obstacles.push(obs);
		game.addChild(obs);
	}
}
// Helper: update score
function updateScore(val) {
	score = val;
	scoreTxt.setText(score);
}
// Touch/drag/swipe handling
game.down = function (x, y, obj) {
	swipeStartX = x;
	swipeStartY = y;
	swipeActive = true;
	dragNode = playerCar;
};
game.move = function (x, y, obj) {
	// Only handle swipe if active
	if (!swipeActive) return;
	if (!dragNode) return;
	var dx = x - swipeStartX;
	var dy = y - swipeStartY;
	// Only consider horizontal swipes, ignore vertical
	if (Math.abs(dx) > 80 && Math.abs(dx) > Math.abs(dy)) {
		var newLane = playerCar.lane;
		if (dx < 0 && playerCar.lane > 0) {
			newLane = playerCar.lane - 1;
		} else if (dx > 0 && playerCar.lane < laneCount - 1) {
			newLane = playerCar.lane + 1;
		}
		if (newLane !== playerCar.lane) {
			playerCar.setLane(newLane);
			LK.getSound('swipe').play();
			swipeActive = false;
			dragNode = null;
		}
	}
};
game.up = function (x, y, obj) {
	swipeActive = false;
	dragNode = null;
};
// Main game update loop
game.update = function () {
	ticksSinceStart++;
	// Only increase game speed after score reaches 50
	if (score >= 50) {
		if (ticksSinceStart % 60 === 0 && gameSpeed < 4) {
			// Increase speed every second, and allow it to go higher
			if (gameSpeed < 2) {
				gameSpeed += 0.08;
			} else if (gameSpeed < 3) {
				gameSpeed += 0.12;
			} else {
				gameSpeed += 0.18;
			}
			if (gameSpeed > 4) gameSpeed = 4;
		}
	} else {
		gameSpeed = 1;
	}
	// Move lane dividers, loop to top
	for (var i = 0; i < laneDividers.length; i++) {
		var div = laneDividers[i];
		div.update();
		if (div.y > 2732 + 60) {
			div.y -= dividerSpacing * 10;
		}
	}
	// Spawn enemies/obstacles every 40-60 ticks, randomize
	spawnTick++;
	var spawnInterval = 40 + Math.floor(Math.random() * 20);
	if (spawnTick > spawnInterval) {
		spawnObstacleOrEnemy();
		spawnTick = 0;
	}
	// Update enemy cars
	for (var i = enemyCars.length - 1; i >= 0; i--) {
		var enemy = enemyCars[i];
		enemy.update();
		// Off screen
		if (enemy.y > 2732 + 300) {
			enemy.destroy();
			enemyCars.splice(i, 1);
			updateScore(score + 1);
			continue;
		}
		// Collision with player
		if (enemy.intersects(playerCar)) {
			LK.getSound('crash').play();
			LK.effects.flashScreen(0xff0000, 800);
			LK.showGameOver();
			return;
		}
	}
	// Update obstacles
	for (var j = obstacles.length - 1; j >= 0; j--) {
		var obs = obstacles[j];
		obs.update();
		// Off screen
		if (obs.y > 2732 + 200) {
			obs.destroy();
			obstacles.splice(j, 1);
			updateScore(score + 1);
			continue;
		}
		// Collision with player
		if (obs.intersects(playerCar)) {
			LK.getSound('crash').play();
			LK.effects.flashScreen(0xff0000, 800);
			LK.showGameOver();
			return;
		}
	}
};
// Center score text at top, avoid top left 100x100
scoreTxt.x = LK.gui.top.width / 2;
scoreTxt.y = 40;

===================================================================
--- original.js
+++ change.js
@@ -203,19 +203,23 @@
 };
 // Main game update loop
 game.update = function () {
 	ticksSinceStart++;
-	// Gradually increase game speed, ramp up faster for more challenge
-	if (ticksSinceStart % 60 === 0 && gameSpeed < 4) {
-		// Increase speed every second, and allow it to go higher
-		if (gameSpeed < 2) {
-			gameSpeed += 0.08;
-		} else if (gameSpeed < 3) {
-			gameSpeed += 0.12;
-		} else {
-			gameSpeed += 0.18;
+	// Only increase game speed after score reaches 50
+	if (score >= 50) {
+		if (ticksSinceStart % 60 === 0 && gameSpeed < 4) {
+			// Increase speed every second, and allow it to go higher
+			if (gameSpeed < 2) {
+				gameSpeed += 0.08;
+			} else if (gameSpeed < 3) {
+				gameSpeed += 0.12;
+			} else {
+				gameSpeed += 0.18;
+			}
+			if (gameSpeed > 4) gameSpeed = 4;
 		}
-		if (gameSpeed > 4) gameSpeed = 4;
+	} else {
+		gameSpeed = 1;
 	}
 	// Move lane dividers, loop to top
 	for (var i = 0; i < laneDividers.length; i++) {
 		var div = laneDividers[i];