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

/**** 
* Classes
****/ 
// Plane class
var Plane = Container.expand(function () {
	var self = Container.call(this);
	var planeSprite = self.attachAsset('plane', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Physics
	self.vy = 0; // vertical velocity
	self.gravity = 1.2; // gravity per frame
	self.flapStrength = -22; // negative for upward
	// Flap method
	self.flap = function () {
		self.vy = self.flapStrength;
		// Animate a quick upward tilt
		tween.stop(planeSprite, {
			rotation: true
		});
		planeSprite.rotation = -0.25;
		tween(planeSprite, {
			rotation: 0.15
		}, {
			duration: 350,
			easing: tween.easeOut
		});
	};
	// Update method
	self.update = function () {
		self.vy += self.gravity;
		self.y += self.vy;
		// Clamp rotation based on vy
		var targetRot = Math.max(-0.3, Math.min(0.4, self.vy / 40));
		planeSprite.rotation += (targetRot - planeSprite.rotation) * 0.2;
	};
	return self;
});
// TowerPair class (top and bottom towers with a gap)
var TowerPair = Container.expand(function () {
	var self = Container.call(this);
	// Constants
	var towerWidth = 220;
	var towerHeight = 900;
	var gapHeight = 520;
	// Top tower
	var topTower = self.attachAsset('tower', {
		anchorX: 0.5,
		anchorY: 1.0
	});
	// Bottom tower
	var bottomTower = self.attachAsset('tower', {
		anchorX: 0.5,
		anchorY: 0.0
	});
	// Set positions
	self.setGapY = function (gapY) {
		// Clamp gapY so that the gap is always fully on screen, and towers start exactly at the top and bottom
		var minGapY = gapHeight / 2;
		var maxGapY = GAME_HEIGHT - GROUND_HEIGHT - gapHeight / 2;
		if (gapY < minGapY) gapY = minGapY;
		if (gapY > maxGapY) gapY = maxGapY;
		// Place top tower so its bottom aligns with the top of the gap, and its top touches the top of the screen
		topTower.x = 0;
		topTower.y = gapY - gapHeight / 2;
		topTower.height = topTower.y; // The anchorY is 1.0, so height stretches from y up to 0
		if (topTower.height < 0) topTower.height = 0;
		// Place bottom tower so its top aligns with the bottom of the gap, and its bottom touches the ground
		bottomTower.x = 0;
		bottomTower.y = gapY + gapHeight / 2;
		bottomTower.height = GAME_HEIGHT - GROUND_HEIGHT - bottomTower.y;
		if (bottomTower.height < 0) bottomTower.height = 0;
	};
	// For collision detection
	self.getTopTower = function () {
		return topTower;
	};
	self.getBottomTower = function () {
		return bottomTower;
	};
	// For scoring
	self.passed = false;
	// Add update method: top tower rotates 180deg, bottom tower is pinned
	self.update = function () {
		if (self.lastX === undefined) self.lastX = self.x;
		// Top tower: rotate 180deg (PI radians)
		self.getTopTower().rotation = Math.PI;
		// Bottom tower: no rotation
		self.getBottomTower().rotation = 0;
		self.lastX = self.x;
	};
	return self;
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	// No title, no description
	backgroundColor: 0x87ceeb
});

/**** 
* Game Code
****/ 
// Sound: hit
// Sound: point
// Ground: brown box, 2048x120
// Tower: green box, 220x900
// Plane: yellow box, 120x80
// Game constants
var GAME_WIDTH = 2048;
var GAME_HEIGHT = 2732;
var GROUND_HEIGHT = 120;
var PLANE_START_X = 600;
var PLANE_START_Y = 1100;
var TOWER_GAP = 520;
var TOWER_WIDTH = 220;
var TOWER_HEIGHT = 900;
var TOWER_MIN_Y = 600 + TOWER_GAP / 2;
var TOWER_MAX_Y = GAME_HEIGHT - GROUND_HEIGHT - 400 - TOWER_GAP / 2;
var TOWER_INTERVAL = 700; // horizontal distance between towers
var TOWER_SPEED = 14; // px per frame
// Game state
var plane;
var towers = [];
var ground;
var score = 0;
var scoreTxt;
var gameStarted = false;
var gameOver = false;
var lastTowerX = 0;
// Add ground
ground = LK.getAsset('ground', {
	anchorX: 0,
	anchorY: 0,
	x: 0,
	y: GAME_HEIGHT - GROUND_HEIGHT
});
game.addChild(ground);
// Add plane
plane = new Plane();
game.addChild(plane);
plane.x = PLANE_START_X;
plane.y = PLANE_START_Y;
// Add score text
scoreTxt = new Text2('0', {
	size: 150,
	fill: 0xFFFFFF
});
scoreTxt.anchor.set(0.5, 0);
LK.gui.top.addChild(scoreTxt);
// Helper: reset game state
function resetGame() {
	// Remove towers
	for (var i = 0; i < towers.length; i++) {
		towers[i].destroy();
	}
	towers = [];
	// Reset plane
	plane.x = PLANE_START_X;
	plane.y = PLANE_START_Y;
	plane.vy = 0;
	// Reset score
	score = 0;
	scoreTxt.setText(score);
	// Reset state
	gameStarted = false;
	gameOver = false;
	lastTowerX = GAME_WIDTH + 600;
	// Add initial towers
	for (var i = 0; i < 3; i++) {
		spawnTower(GAME_WIDTH + 600 + i * TOWER_INTERVAL);
	}
}
// Helper: spawn a tower pair at x
function spawnTower(x) {
	var gapY = TOWER_MIN_Y + Math.random() * (TOWER_MAX_Y - TOWER_MIN_Y);
	var towerPair = new TowerPair();
	towerPair.x = x;
	towerPair.setGapY(gapY);
	game.addChild(towerPair);
	towers.push(towerPair);
}
// Start game
resetGame();
// Input: tap anywhere to flap
game.down = function (x, y, obj) {
	if (gameOver) return;
	if (!gameStarted) {
		gameStarted = true;
	}
	plane.flap();
};
// Main update loop
game.update = function () {
	if (gameOver) return;
	if (gameStarted) {
		// Move towers
		for (var i = towers.length - 1; i >= 0; i--) {
			var t = towers[i];
			t.x -= TOWER_SPEED;
			// Update tower (for rotation)
			if (typeof t.update === "function") t.update();
			// Remove towers off screen
			if (t.x < -TOWER_WIDTH) {
				t.destroy();
				towers.splice(i, 1);
			}
		}
		// Spawn new towers
		if (towers.length === 0 || towers[towers.length - 1].x < GAME_WIDTH - TOWER_INTERVAL) {
			spawnTower(GAME_WIDTH + TOWER_WIDTH);
		}
		// Plane physics
		plane.update();
		// Collision: ground
		if (plane.y + 40 > GAME_HEIGHT - GROUND_HEIGHT) {
			plane.y = GAME_HEIGHT - GROUND_HEIGHT - 40;
			endGame();
			return;
		}
		// Collision: ceiling
		if (plane.y - 40 < 0) {
			plane.y = 40;
			plane.vy = 0;
		}
		// Collision: towers
		for (var i = 0; i < towers.length; i++) {
			var t = towers[i];
			// Only check if in range
			if (Math.abs(t.x - plane.x) < TOWER_WIDTH) {
				// Top
				if (plane.intersects(t.getTopTower()) || plane.intersects(t.getBottomTower())) {
					endGame();
					return;
				}
			}
			// Scoring: passed tower
			if (!t.passed && t.x + TOWER_WIDTH / 2 < plane.x) {
				t.passed = true;
				score += 1;
				scoreTxt.setText(score);
				LK.getSound('point').play();
			}
		}
	} else {
		// Idle: plane bobs up and down
		plane.y = PLANE_START_Y + Math.sin(LK.ticks / 30) * 30;
		plane.vy = 0;
	}
};
// End game
function endGame() {
	if (gameOver) return;
	gameOver = true;
	LK.getSound('hit').play();
	LK.effects.flashScreen(0xff0000, 600);
	LK.showGameOver();
}
// No drag or move needed for this game

===================================================================
--- original.js
+++ change.js
@@ -102,9 +102,9 @@
 * Initialize Game
 ****/ 
 var game = new LK.Game({
 	// No title, no description
-	backgroundColor: 0x000000
+	backgroundColor: 0x87ceeb
 });
 
 /**** 
 * Game Code