/**** 
* Plugins
****/ 
var tween = LK.import("@upit/tween.v1");
var storage = LK.import("@upit/storage.v1", {
	coins: 0,
	unlockedSkins: [],
	selectedSkin: 0
});

/**** 
* Classes
****/ 
// Ball class
var Ball = Container.expand(function () {
	var self = Container.call(this);
	// Ball color index: 0=red, 1=blue, 2=green, 3=yellow
	self.colorIndex = 0;
	self.colors = ['red', 'blue', 'green', 'yellow'];
	self.asset = null;
	// Attach initial asset
	self.setColor = function (idx) {
		if (self.asset) {
			self.removeChild(self.asset);
		}
		self.colorIndex = idx;
		var colorName = self.colors[self.colorIndex];
		self.asset = self.attachAsset('ball_' + colorName, {
			anchorX: 0.5,
			anchorY: 0.5
		});
	};
	self.cycleColor = function () {
		var next = (self.colorIndex + 1) % self.colors.length;
		self.setColor(next);
	};
	// For simple trail effect (MVP: just a quick flash)
	self.flash = function () {
		tween(self.asset, {
			alpha: 0.5
		}, {
			duration: 60,
			easing: tween.linear,
			onFinish: function onFinish() {
				tween(self.asset, {
					alpha: 1
				}, {
					duration: 80
				});
			}
		});
	};
	// Set initial color
	self.setColor(0);
	return self;
});
// Coin class
var Coin = Container.expand(function () {
	var self = Container.call(this);
	self.asset = self.attachAsset('coin', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.update = function () {
		// MVP: no animation
	};
	return self;
});
// Platform class
var Platform = Container.expand(function () {
	var self = Container.call(this);
	// Color index: 0=red, 1=blue, 2=green, 3=yellow
	self.colorIndex = 0;
	self.colors = ['red', 'blue', 'green', 'yellow'];
	self.asset = null;
	// For moving platforms (future)
	self.vx = 0;
	self.setColor = function (idx) {
		if (self.asset) {
			self.removeChild(self.asset);
		}
		self.colorIndex = idx;
		var colorName = self.colors[self.colorIndex];
		self.asset = self.attachAsset('platform_' + colorName, {
			anchorX: 0.5,
			anchorY: 0.5
		});
	};
	// For MVP, platforms are static
	self.update = function () {
		if (self.vx !== 0) {
			self.x += self.vx;
			// Bounce off edges
			if (self.x < self.asset.width / 2) {
				self.x = self.asset.width / 2;
				self.vx *= -1;
			}
			if (self.x > 2048 - self.asset.width / 2) {
				self.x = 2048 - self.asset.width / 2;
				self.vx *= -1;
			}
		}
	};
	// Set initial color
	self.setColor(0);
	return self;
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x181c20
});

/**** 
* Game Code
****/ 
// Music (stub, not played in MVP)
// SFX
// Ball colors (platforms and ball)
// --- Game variables ---
var ball = null;
var platforms = [];
var coins = [];
var score = 0;
var coinCount = 0;
var platformSpacing = 340; // vertical distance between platforms
var platformSpeed = 12; // initial fall speed
var gravity = 1.1; // increases as score increases
var bounceVelocity = -38; // initial bounce velocity
var ballVy = 0;
var isFalling = true;
var currentPlatformIdx = 0;
var lastTapTick = 0;
var gameStarted = false;
var dragNode = null; // not used, but required by guidelines
var lastIntersecting = false;
var canTap = true; // prevent double tap in one frame
// GUI
var scoreTxt = new Text2('0', {
	size: 120,
	fill: '#fff'
});
scoreTxt.anchor.set(0.5, 0);
LK.gui.top.addChild(scoreTxt);
var coinTxt = new Text2('0', {
	size: 80,
	fill: '#ffd700'
});
coinTxt.anchor.set(1, 0);
coinTxt.x = -40;
coinTxt.y = 20;
LK.gui.topRight.addChild(coinTxt);
// --- Helper functions ---
function getRandomColorIdx() {
	// 0=red, 1=blue, 2=green, 3=yellow
	return Math.floor(Math.random() * 4);
}
function spawnPlatform(y, colorIdx) {
	var plat = new Platform();
	plat.setColor(colorIdx);
	plat.x = 2048 / 2;
	plat.y = y;
	// MVP: no moving platforms
	platforms.push(plat);
	game.addChild(plat);
	return plat;
}
function spawnCoin(x, y) {
	var c = new Coin();
	c.x = x;
	c.y = y - 60;
	coins.push(c);
	game.addChild(c);
	return c;
}
function resetGameVars() {
	score = 0;
	coinCount = 0;
	platformSpeed = 12;
	gravity = 1.1;
	bounceVelocity = -38;
	ballVy = 0;
	isFalling = true;
	currentPlatformIdx = 0;
	lastTapTick = 0;
	canTap = true;
	gameStarted = false;
	lastIntersecting = false;
	// Remove old platforms and coins
	for (var i = 0; i < platforms.length; ++i) platforms[i].destroy();
	for (var i = 0; i < coins.length; ++i) coins[i].destroy();
	platforms = [];
	coins = [];
	// Remove ball
	if (ball) {
		ball.destroy();
		ball = null;
	}
}
// --- Game start ---
function startGame() {
	resetGameVars();
	// Ball
	ball = new Ball();
	ball.x = 2048 / 2;
	ball.y = 600;
	game.addChild(ball);
	// Platforms: fill screen from the bottom up
	var y = 2732 - 120; // Start near the bottom of the screen
	for (var i = 0; i < 8; ++i) {
		var colorIdx = getRandomColorIdx();
		var plat = spawnPlatform(y, colorIdx);
		// Place a coin on every 3rd platform
		if (i > 0 && i % 3 === 0) {
			spawnCoin(plat.x, plat.y);
		}
		y -= platformSpacing;
	}
	currentPlatformIdx = 0;
	isFalling = true;
	ballVy = 0;
	score = 0;
	coinCount = 0;
	scoreTxt.setText('0');
	coinTxt.setText(storage.coins || 0);
	gameStarted = true;
}
// --- Input: tap to cycle color ---
game.down = function (x, y, obj) {
	if (!gameStarted) {
		startGame();
		return;
	}
	if (!canTap) return;
	canTap = false;
	if (ball) {
		ball.cycleColor();
		ball.flash();
	}
	lastTapTick = LK.ticks;
};
game.up = function (x, y, obj) {
	canTap = true;
};
// --- Main game loop ---
game.update = function () {
	if (!gameStarted) return;
	// Ball physics
	if (isFalling) {
		ballVy += gravity;
		ball.y += ballVy;
	}
	// Move platforms upward to simulate ball falling
	var moveUp = platformSpeed;
	for (var i = 0; i < platforms.length; ++i) {
		platforms[i].y -= moveUp;
		platforms[i].update();
	}
	for (var i = 0; i < coins.length; ++i) {
		coins[i].y -= moveUp;
		coins[i].update();
	}
	// Remove platforms/coins that go off top
	for (var i = platforms.length - 1; i >= 0; --i) {
		if (platforms[i].y < -100) {
			platforms[i].destroy();
			platforms.splice(i, 1);
		}
	}
	for (var i = coins.length - 1; i >= 0; --i) {
		if (coins[i].y < -100) {
			coins[i].destroy();
			coins.splice(i, 1);
		}
	}
	// Spawn new platforms as needed
	var lastPlat = platforms[platforms.length - 1];
	if (lastPlat && lastPlat.y < 2732 - platformSpacing) {
		var colorIdx = getRandomColorIdx();
		var plat = spawnPlatform(lastPlat.y + platformSpacing, colorIdx);
		// Place a coin on every 3rd platform
		if ((score + platforms.length) % 3 === 0) {
			spawnCoin(plat.x, plat.y);
		}
	}
	// Ball collision with platform (only check nearest platform)
	var hit = false;
	for (var i = 0; i < platforms.length; ++i) {
		var plat = platforms[i];
		// Only check platforms below ball
		if (plat.y > ball.y && plat.y - ball.y < 120) {
			// Check horizontal overlap
			var dx = Math.abs(ball.x - plat.x);
			if (dx < plat.asset.width / 2 - 30) {
				// Check vertical overlap
				var dy = Math.abs(ball.y - plat.y);
				if (dy < 90) {
					// Ball is landing on platform
					hit = true;
					// Only trigger bounce if falling
					if (ballVy > 0) {
						// Color match?
						if (ball.colorIndex === plat.colorIndex) {
							// Success!
							ballVy = bounceVelocity;
							isFalling = true;
							score += 1;
							scoreTxt.setText(score);
							LK.setScore(score);
							LK.getSound('bounce').play();
							// Flash ball
							ball.flash();
							// Increase difficulty
							if (score % 10 === 0) {
								platformSpeed += 1.5;
								gravity += 0.12;
							}
						} else {
							// Fail: wrong color
							LK.getSound('fail').play();
							LK.effects.flashScreen(0xff0000, 600);
							LK.showGameOver();
							return;
						}
					}
				}
			}
		}
	}
	// Ball falls off bottom
	if (ball.y > 2732 + 100) {
		LK.getSound('fail').play();
		LK.effects.flashScreen(0xff0000, 600);
		LK.showGameOver();
		return;
	}
	// Coin collection
	for (var i = coins.length - 1; i >= 0; --i) {
		var c = coins[i];
		var dx = Math.abs(ball.x - c.x);
		var dy = Math.abs(ball.y - c.y);
		if (dx < 90 && dy < 90) {
			// Collect coin
			LK.getSound('coin').play();
			c.destroy();
			coins.splice(i, 1);
			coinCount += 1;
			storage.coins = (storage.coins || 0) + 1;
			coinTxt.setText(storage.coins);
			// Simple coin pop
			// (future: animate)
		}
	}
};
// --- Game over / win handling is automatic by LK ---
// --- Start screen: tap to start ---
startGame();

===================================================================
--- original.js
+++ change.js
@@ -206,18 +206,18 @@
 	ball = new Ball();
 	ball.x = 2048 / 2;
 	ball.y = 600;
 	game.addChild(ball);
-	// Platforms: fill screen
-	var y = 1000;
+	// Platforms: fill screen from the bottom up
+	var y = 2732 - 120; // Start near the bottom of the screen
 	for (var i = 0; i < 8; ++i) {
 		var colorIdx = getRandomColorIdx();
 		var plat = spawnPlatform(y, colorIdx);
 		// Place a coin on every 3rd platform
 		if (i > 0 && i % 3 === 0) {
 			spawnCoin(plat.x, plat.y);
 		}
-		y += platformSpacing;
+		y -= platformSpacing;
 	}
 	currentPlatformIdx = 0;
 	isFalling = true;
 	ballVy = 0;