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

/**** 
* Classes
****/ 
var Coin = Container.expand(function (startX, startY) {
	var self = Container.call(this);
	var coinGraphics = self.attachAsset('coin', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.collected = false;
	self.x = startX || 400;
	self.y = startY || 2300;
	self.update = function () {
		if (!self.collected) {
			self.rotation += 0.1;
		}
	};
	self.collect = function () {
		if (!self.collected) {
			self.collected = true;
			self.alpha = 0;
			LK.setScore(LK.getScore() + 10);
			LK.getSound('coin_collect').play();
		}
	};
	return self;
});
var Enemy = Container.expand(function (startX, startY) {
	var self = Container.call(this);
	var enemyGraphics = self.attachAsset('enemy', {
		anchorX: 0.5,
		anchorY: 1
	});
	self.velocityX = -1;
	self.velocityY = 0;
	self.gravity = 0.5;
	self.alive = true;
	self.x = startX || 800;
	self.y = startY || 2400;
	self.update = function () {
		if (!self.alive) return;
		// Apply gravity
		self.velocityY += self.gravity;
		// Update position
		self.x += self.velocityX;
		self.y += self.velocityY;
		// Ground collision
		if (self.y >= 2400) {
			self.y = 2400;
			self.velocityY = 0;
		}
		// Platform collision
		for (var i = 0; i < platforms.length; i++) {
			var platform = platforms[i];
			if (self.intersects(platform) && self.velocityY > 0) {
				if (self.y - 25 <= platform.y - 20) {
					self.y = platform.y - 20;
					self.velocityY = 0;
					break;
				}
			}
		}
		// Reverse direction at edges
		if (self.x < 50 || self.x > levelWidth - 50) {
			self.velocityX = -self.velocityX;
		}
	};
	self.defeat = function () {
		self.alive = false;
		self.alpha = 0.5;
		LK.getSound('enemy_hit').play();
		LK.setTimeout(function () {
			self.destroy();
		}, 500);
	};
	return self;
});
var Platform = Container.expand(function (startX, startY, width) {
	var self = Container.call(this);
	self.platformWidth = width || 200;
	var platformGraphics = self.attachAsset('platform', {
		anchorX: 0.5,
		anchorY: 0.5,
		width: self.platformWidth
	});
	self.x = startX || 400;
	self.y = startY || 2000;
	return self;
});
var Player = Container.expand(function () {
	var self = Container.call(this);
	var playerGraphics = self.attachAsset('player', {
		anchorX: 0.5,
		anchorY: 1
	});
	self.velocityX = 0;
	self.velocityY = 0;
	self.gravity = 0.5;
	self.jumpPower = -12;
	self.speed = 4;
	self.onGround = false;
	self.lastOnGround = false;
	self.x = 200;
	self.y = 2400;
	self.update = function () {
		// Auto-move forward for runner game
		self.velocityX = self.speed;
		// Apply gravity
		self.velocityY += self.gravity;
		// Update position
		self.x += self.velocityX;
		self.y += self.velocityY;
		// Ground collision
		if (self.y >= 2400) {
			self.y = 2400;
			self.velocityY = 0;
			self.onGround = true;
		} else {
			self.onGround = false;
		}
		// Platform collision
		for (var i = 0; i < platforms.length; i++) {
			var platform = platforms[i];
			if (self.intersects(platform) && self.velocityY > 0) {
				if (self.y - 60 <= platform.y - 20) {
					self.y = platform.y - 20;
					self.velocityY = 0;
					self.onGround = true;
					break;
				}
			}
		}
		// Update camera to follow player
		cameraX = self.x - 1024;
		if (cameraX < 0) cameraX = 0;
		if (cameraX > levelWidth - 2048) cameraX = levelWidth - 2048;
		self.lastOnGround = self.onGround;
	};
	self.jump = function () {
		if (self.onGround) {
			self.velocityY = self.jumpPower;
			self.onGround = false;
			LK.getSound('jump').play();
		}
	};
	self.moveLeft = function () {
		self.velocityX = -self.speed;
	};
	self.moveRight = function () {
		self.velocityX = self.speed;
	};
	self.stop = function () {
		self.velocityX = 0;
	};
	return self;
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x87ceeb
});

/**** 
* Game Code
****/ 
// Game variables
var levelWidth = 4000;
var cameraX = 0;
var platforms = [];
var enemies = [];
var coins = [];
var player = new Player();
var gameContainer = new Container();
// Touch controls - only jump for runner game
game.addChild(gameContainer);
gameContainer.addChild(player);
// Create ground
var ground = gameContainer.attachAsset('ground', {
	x: 0,
	y: 2460,
	width: levelWidth,
	anchorX: 0,
	anchorY: 0
});
// Create platforms
var platformData = [{
	x: 600,
	y: 2300,
	width: 200
}, {
	x: 1000,
	y: 2250,
	width: 200
}, {
	x: 1400,
	y: 2200,
	width: 200
}, {
	x: 1800,
	y: 2280,
	width: 200
}, {
	x: 2200,
	y: 2240,
	width: 200
}, {
	x: 2600,
	y: 2180,
	width: 200
}, {
	x: 3000,
	y: 2150,
	width: 200
}, {
	x: 3400,
	y: 2220,
	width: 200
}];
for (var i = 0; i < platformData.length; i++) {
	var platData = platformData[i];
	var platform = new Platform(platData.x, platData.y, platData.width);
	platforms.push(platform);
	gameContainer.addChild(platform);
}
// Create enemies
var enemyData = [{
	x: 900,
	y: 2400
}, {
	x: 1500,
	y: 2400
}, {
	x: 2300,
	y: 2400
}, {
	x: 3200,
	y: 2400
}];
for (var i = 0; i < enemyData.length; i++) {
	var enemyPos = enemyData[i];
	var enemy = new Enemy(enemyPos.x, enemyPos.y);
	enemies.push(enemy);
	gameContainer.addChild(enemy);
}
// Create coins
var coinData = [{
	x: 400,
	y: 2350
}, {
	x: 700,
	y: 2250
}, {
	x: 1100,
	y: 2200
}, {
	x: 1500,
	y: 2150
}, {
	x: 1900,
	y: 2230
}, {
	x: 2300,
	y: 2190
}, {
	x: 2700,
	y: 2130
}, {
	x: 3100,
	y: 2100
}, {
	x: 3500,
	y: 2170
}];
for (var i = 0; i < coinData.length; i++) {
	var coinPos = coinData[i];
	var coin = new Coin(coinPos.x, coinPos.y);
	coins.push(coin);
	gameContainer.addChild(coin);
}
// Create finish flag
var flag = gameContainer.attachAsset('flag', {
	x: 3800,
	y: 2340,
	anchorX: 0.5,
	anchorY: 1
});
// Create UI
var scoreText = new Text2('Score: 0', {
	size: 48,
	fill: '#ffffff'
});
scoreText.anchor.set(0, 0);
scoreText.x = 50;
scoreText.y = 50;
LK.gui.topLeft.addChild(scoreText);
var instructionText = new Text2('Tap JUMP to jump! Avoid enemies and collect coins!', {
	size: 32,
	fill: '#ffffff'
});
instructionText.anchor.set(0.5, 0);
instructionText.x = 1024;
instructionText.y = 100;
LK.gui.top.addChild(instructionText);
// Control areas for mobile - only jump button for runner game
var jumpControl = new Container();
var jumpControlGraphics = jumpControl.attachAsset('platform', {
	x: 1024,
	y: 2500,
	width: 300,
	height: 150,
	alpha: 0.3,
	color: 0xff6600,
	anchorX: 0.5,
	anchorY: 0
});
game.addChild(jumpControl);
// Add jump button text
var jumpText = new Text2('JUMP', {
	size: 40,
	fill: '#ffffff'
});
jumpText.anchor.set(0.5, 0.5);
jumpText.x = 1024;
jumpText.y = 2575;
game.addChild(jumpText);
// Keyboard controls not supported in LK engine - using touch controls only
jumpControl.down = function (x, y, obj) {
	player.jump();
};
game.update = function () {
	// Update player (auto-running)
	player.update();
	// Update enemies
	for (var i = enemies.length - 1; i >= 0; i--) {
		var enemy = enemies[i];
		enemy.update();
	}
	// Update coins
	for (var i = 0; i < coins.length; i++) {
		var coin = coins[i];
		coin.update();
	}
	// Check collisions with enemies
	for (var i = enemies.length - 1; i >= 0; i--) {
		var enemy = enemies[i];
		if (enemy.alive && player.intersects(enemy)) {
			if (player.velocityY > 0 && player.y < enemy.y - 30) {
				// Player jumped on enemy
				enemy.defeat();
				enemies.splice(i, 1);
				player.velocityY = -10; // Bounce
				LK.setScore(LK.getScore() + 50);
			} else {
				// Player hit enemy
				LK.getSound('game_over').play();
				LK.showGameOver();
				return;
			}
		}
	}
	// Check collisions with coins
	for (var i = coins.length - 1; i >= 0; i--) {
		var coin = coins[i];
		if (!coin.collected && player.intersects(coin)) {
			coin.collect();
			coins.splice(i, 1);
		}
	}
	// Check if player reached flag
	if (player.intersects(flag)) {
		LK.showYouWin();
		return;
	}
	// Check if player fell off screen
	if (player.y > 2800) {
		LK.getSound('game_over').play();
		LK.showGameOver();
		return;
	}
	// Update camera
	gameContainer.x = -cameraX;
	// Update score display
	scoreText.setText('Score: ' + LK.getScore());
};

===================================================================
--- original.js
+++ change.js
@@ -126,9 +126,9 @@
 		// Platform collision
 		for (var i = 0; i < platforms.length; i++) {
 			var platform = platforms[i];
 			if (self.intersects(platform) && self.velocityY > 0) {
-				if (self.y - 40 <= platform.y - 20) {
+				if (self.y - 60 <= platform.y - 20) {
 					self.y = platform.y - 20;
 					self.velocityY = 0;
 					self.onGround = true;
 					break;
@@ -350,9 +350,9 @@
 	// Check collisions with enemies
 	for (var i = enemies.length - 1; i >= 0; i--) {
 		var enemy = enemies[i];
 		if (enemy.alive && player.intersects(enemy)) {
-			if (player.velocityY > 0 && player.y < enemy.y - 20) {
+			if (player.velocityY > 0 && player.y < enemy.y - 30) {
 				// Player jumped on enemy
 				enemy.defeat();
 				enemies.splice(i, 1);
 				player.velocityY = -10; // Bounce