/**** 
* Classes
****/ 
var Block = Container.expand(function (board) {
	var self = Container.call(this);
	var hsvToRgb = function hsvToRgb(h, s, v) {
		var r, g, b;
		var i = Math.floor(h * 6);
		var f = h * 6 - i;
		var p = v * (1 - s);
		var q = v * (1 - f * s);
		var t = v * (1 - (1 - f) * s);
		switch (i % 6) {
			case 0:
				r = v, g = t, b = p;
				break;
			case 1:
				r = q, g = v, b = p;
				break;
			case 2:
				r = p, g = v, b = t;
				break;
			case 3:
				r = p, g = q, b = v;
				break;
			case 4:
				r = t, g = p, b = v;
				break;
			case 5:
				r = v, g = p, b = q;
				break;
		}
		return (Math.round(r * 255) << 16) + (Math.round(g * 255) << 8) + Math.round(b * 255);
	};
	var ShapeTypes = {
		SINGLE: [[1]],
		TRI: [[1, 1, 1]],
		QUAD: [[1, 1, 1, 1]],
		LSHAPE: [[1, 0, 0], [1, 0, 0], [1, 1, 1]],
		BLOCK: [[1, 1], [1, 1]],
		SMALLLSHAPE: [[1, 0], [1, 1]],
		T: [[0, 1, 0], [1, 1, 1]]
	};
	var shapes = Object.values(ShapeTypes);
	var offset = Math.floor(Math.random() * shapes.length);
	self.shape = shapes[offset];
	var hue = offset % shapes.length / shapes.length;
	self.color = hsvToRgb(hue, 0.6, 1);
	self.rotateShapeRandomly = function () {
		var rotations = Math.floor(Math.random() * 4);
		for (var r = 0; r < rotations; r++) {
			self.shape = self.shape[0].map(function (val, index) {
				return self.shape.map(function (row) {
					return row[index];
				}).reverse();
			});
		}
	};
	self.rotateShapeRandomly();
	self.blocks = [];
	var background = self.attachAsset('background', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	background.alpha = 0;
	var blockSize = 160;
	background.width = 4 * blockSize;
	background.height = 4 * blockSize;
	self.addChild(background);
	self.offsetX = 0;
	self.offsetY = 0;
	var blockOffsetX = (background.width / 2 - self.shape[0].length * blockSize) / 2 - blockSize / 2;
	var blockOffsetY = (background.height / 2 - self.shape.length * blockSize) / 2 - blockSize / 2;
	for (var i = 0; i < self.shape.length; i++) {
		for (var j = 0; j < self.shape[i].length; j++) {
			if (self.shape[i][j] === 1) {
				var block = self.attachAsset('block', {
					anchorX: 0.5,
					anchorY: 0.5
				});
				block.tint = self.color;
				block.width = blockSize;
				block.height = blockSize;
				block.x = j * blockSize + blockOffsetX;
				block.y = i * blockSize + blockOffsetY;
				self.blocks.push(block);
				self.addChild(block);
			}
		}
	}
	self.startX = 0;
	self.startY = 0;
	self.moveTowardsHomePosition = function () {
		var dx = self.startX - self.x;
		var dy = self.startY - self.y;
		var distance = Math.sqrt(dx * dx + dy * dy);
		if (distance > 1) {
			self.x += dx * 0.3;
			self.y += dy * 0.3;
		} else {
			self.x = self.startX;
			self.y = self.startY;
		}
	};
	var currentX = 0;
	var currentY = 0;
	self.moveToDragTarget = function () {
		var ox = -this.targetX;
		var oy = (LK.is.mobile ? 400 : 0) - this.targetY;
		this.targetX += ox / 5;
		this.targetY += oy / 5;
		this.x = currentX - this.targetX;
		this.y = currentY - this.targetY;
	};
	self._move_migrated = function (x, y) {
		currentX = x;
		currentY = y;
		self.x = x - this.targetX;
		self.y = y - this.targetY;
	};
	self.setStartPosition = function (x, y) {
		self.startX = x;
		self.startY = y;
	};
	self.getOverlappingCells = function () {
		var cells = [];
		var boardPos = {
			x: -board.x + self.x + 160 * 4 + blockOffsetX + 160,
			y: -board.y + self.y + 160 * 4 + blockOffsetY + 160
		};
		var startX = Math.floor(boardPos.x / 160);
		var startY = Math.floor(boardPos.y / 160);
		for (var i = 0; i < self.shape.length; i++) {
			for (var j = 0; j < self.shape[i].length; j++) {
				if (self.shape[i][j] === 1) {
					var cell = board.grid && board.grid[startY + i] && board.grid[startY + i][startX + j];
					if (cell && !cell.filled) {
						cells.push(cell);
					} else {
						return null;
					}
				}
			}
		}
		return cells;
	};
	self.showOverlap = function () {
		var cells = self.getOverlappingCells();
		if (cells) {
			for (var a = 0; a < cells.length; a++) {
				var cell = cells[a];
				cell.setTint(self.color);
			}
		}
	};
	self.rotateShapeRandomly = function () {
		var rotations = Math.floor(Math.random() * 4);
		for (var r = 0; r < rotations; r++) {
			self.shape = self.shape[0].map(function (val, index) {
				return self.shape.map(function (row) {
					return row[index];
				}).reverse();
			});
		}
	};
});
var Board = Container.expand(function () {
	var self = Container.call(this);
	self.particles = [];
	Board.prototype.spawnParticles = function (x, y, tint) {
		for (var i = 0; i < 10; i++) {
			var particle = new Particle(tint);
			particle.x = x;
			particle.y = y;
			this.particles.push(particle);
			this.addChild(particle);
		}
	};
	var background = self.attachAsset('background', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	background.y = -20;
	background.alpha = .4;
	background.blendMode = 1;
	self.grid = new Array(10).fill(null).map(function () {
		return new Array(10).fill(null);
	});
	var size = 158;
	var totalWidth = 10 * size;
	var totalHeight = 10 * size;
	for (var i = 0; i < 10; i++) {
		for (var j = 0; j < 10; j++) {
			var cell = new Cell();
			cell.x = i * size - totalWidth / 2 + size / 2;
			cell.y = j * size - totalHeight / 2 + size / 2;
			self.grid[j][i] = cell;
			self.addChild(cell);
		}
	}
	self.removeTint = function () {
		for (var i = 0; i < 10; i++) {
			for (var j = 0; j < 10; j++) {
				if (!self.grid[i][j].filled) {
					self.grid[i][j].setTint(0xffffff);
				}
			}
		}
	};
	self.checkLines = function () {
		var rowsRemoved = 0;
		for (var i = 0; i < 10; i++) {
			var rowFilled = true;
			var colFilled = true;
			for (var j = 0; j < 10; j++) {
				if (!self.grid[i][j].filled) {
					rowFilled = false;
				}
				if (!self.grid[j][i].filled) {
					colFilled = false;
				}
			}
			if (rowFilled || colFilled) {
				rowsRemoved += (rowFilled ? 1 : 0) + (colFilled ? 1 : 0);
				for (var j = 0; j < 10; j++) {
					if (rowFilled) {
						self.grid[i][j].setFill(false);
						self.spawnParticles(self.grid[i][j].x, self.grid[i][j].y, self.grid[i][j].getTint());
					}
					if (colFilled) {
						self.grid[j][i].setFill(false);
						self.spawnParticles(self.grid[j][i].x, self.grid[j][i].y, self.grid[j][i].getTint());
					}
				}
			}
		}
		return rowsRemoved;
	};
	self.tick = function () {
		for (var i = self.particles.length - 1; i >= 0; i--) {
			var particle = self.particles[i];
			if (particle) {
				particle.tick();
				if (particle.alpha <= 0) {
					self.particles.splice(i, 1);
				}
			}
		}
	};
	self.placeBlock = function () {};
});
var Cell = Container.expand(function () {
	var self = Container.call(this);
	self.filled = false;
	var empty = self.attachAsset('cell', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	empty.alpha = .8;
	var filled = self.attachAsset('block', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	empty.y = 2;
	self.setFill = function (isFilled) {
		self.filled = isFilled;
		empty.visible = !self.filled;
		filled.visible = self.filled;
	};
	self.getTint = function () {
		return filled.tint;
	};
	self.setTint = function (tint) {
		empty.tint = filled.tint = tint;
	};
	self.setFill(false);
});
var Particle = Container.expand(function (tint) {
	var self = Container.call(this);
	self.tint = tint;
	var particleGraphics = self.attachAsset('particle', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	particleGraphics.rotation = Math.random() * Math.PI * 2;
	particleGraphics.tint = self.tint;
	self.vx = Math.random() * 4 - 2;
	self.vy = Math.random() * 4 - 2;
	self.alpha = 1;
	self.lifetime = 60;
	self.tick = function () {
		self.x += self.vx;
		self.y += self.vy;
		self.alpha -= 1 / self.lifetime;
		if (self.alpha <= 0) {
			self.destroy();
		}
	};
});

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

/**** 
* Game Code
****/ 
var gameBackground = game.attachAsset('gameBackground', {
	anchorX: 0.5,
	anchorY: 0.5
});
gameBackground.x = 2048 / 2;
gameBackground.y = 2732 / 2;
var tilesBackground = game.attachAsset('tileBackground', {
	anchorX: 0.5,
	anchorY: 0.5
});
tilesBackground.y = -20;
tilesBackground.alpha = .4;
tilesBackground.blendMode = 1;
var blocks = [];
var dragTarget;
var board = game.addChild(new Board());
board.x = 2048 / 2;
board.y = 2732 / 2 - 250 + 30;
tilesBackground.x = 2048 / 2;
tilesBackground.y = 2732 - 300;
var targetOffset;
game.createBlock = function (index) {
	var block = new Block(board);
	block.x = 2048 / 2 + (index - 1) * (block.width + 30);
	block.y = 2732 + block.height;
	block.setStartPosition(block.x, 2732 - block.height / 2 - 30);
	blocks.push(block);
	game.addChild(block);
	// Double-tap detection and 90-degree right rotation
	block._lastTapTime = 0;
	block.on('down', function (x, y, obj) {
		var now = Date.now();
		if (now - this._lastTapTime < 350) {
			// Double-tap detected, rotate 90 degrees right
			// Rotate shape 90 degrees right (clockwise) and update logic
			// 1. Rotate the shape array
			var oldShape = this.shape;
			var newShape = [];
			// Handle single-row and single-column blocks correctly
			if (oldShape.length === 1) {
				// Single row (horizontal) -> become single column (vertical)
				for (var j = 0; j < oldShape[0].length; j++) {
					newShape.push([oldShape[0][j]]);
				}
			} else if (oldShape[0].length === 1) {
				// Single column (vertical) -> become single row (horizontal)
				var row = [];
				for (var i = oldShape.length - 1; i >= 0; i--) {
					row.push(oldShape[i][0]);
				}
				newShape.push(row);
			} else {
				// General case: rotate matrix
				for (var j = 0; j < oldShape[0].length; j++) {
					var newRow = [];
					for (var i = oldShape.length - 1; i >= 0; i--) {
						newRow.push(oldShape[i][j]);
					}
					newShape.push(newRow);
				}
			}
			this.shape = newShape;
			// 2. Remove old blocks
			for (var i = 0; i < this.blocks.length; i++) {
				this.removeChild(this.blocks[i]);
			}
			this.blocks = [];
			// 3. Recreate blocks with new shape
			var blockSize = 160;
			var background = this.children[0];
			// Find the anchor cell (first '1' in the old shape)
			var anchorI = 0,
				anchorJ = 0;
			var foundAnchor = false;
			for (var i = 0; i < oldShape.length && !foundAnchor; i++) {
				for (var j = 0; j < oldShape[i].length && !foundAnchor; j++) {
					if (oldShape[i][j] === 1) {
						anchorI = i;
						anchorJ = j;
						foundAnchor = true;
					}
				}
			}
			// After rotation, find the new anchor cell (first '1' in the new shape)
			var newAnchorI = 0,
				newAnchorJ = 0;
			foundAnchor = false;
			for (var i = 0; i < newShape.length && !foundAnchor; i++) {
				for (var j = 0; j < newShape[i].length && !foundAnchor; j++) {
					if (newShape[i][j] === 1) {
						newAnchorI = i;
						newAnchorJ = j;
						foundAnchor = true;
					}
				}
			}
			// Calculate offset so that the anchor cell stays at the same place visually
			var blockOffsetX = (background.width / 2 - this.shape[0].length * blockSize) / 2 - blockSize / 2;
			var blockOffsetY = (background.height / 2 - this.shape.length * blockSize) / 2 - blockSize / 2;
			var anchorDeltaX = (anchorJ - newAnchorJ) * blockSize;
			var anchorDeltaY = (anchorI - newAnchorI) * blockSize;
			for (var i = 0; i < this.shape.length; i++) {
				for (var j = 0; j < this.shape[i].length; j++) {
					if (this.shape[i][j] === 1) {
						var blockAsset = this.attachAsset('block', {
							anchorX: 0.5,
							anchorY: 0.5
						});
						blockAsset.tint = this.color;
						blockAsset.width = blockSize;
						blockAsset.height = blockSize;
						blockAsset.x = j * blockSize + blockOffsetX + anchorDeltaX;
						blockAsset.y = i * blockSize + blockOffsetY + anchorDeltaY;
						this.blocks.push(blockAsset);
						this.addChild(blockAsset);
					}
				}
			}
			// After rotation, update start position and drag offset if needed
			if (typeof this.setStartPosition === "function") {
				this.setStartPosition(this.x, this.y);
			}
			this._lastTapTime = 0; // reset
			return;
		}
		this._lastTapTime = now;
		dragTarget = this;
		var pos = this.toLocal(obj.global);
		var targetPos = game.toLocal(obj.global);
		this.targetX = pos.x;
		this.targetY = pos.y;
		dragTarget._move_migrated(targetPos.x, targetPos.y);
	});
};
game.on('move', function (x, y, obj) {
	if (dragTarget) {
		board.removeTint();
		var pos = game.toLocal(obj.global);
		dragTarget._move_migrated(pos.x, pos.y);
		dragTarget.showOverlap();
	}
});
game.on('up', function (x, y, obj) {
	if (dragTarget) {
		var cells = dragTarget.getOverlappingCells();
		if (cells) {
			for (var a = 0; a < cells.length; a++) {
				cells[a].setFill(true);
				cells[a].setTint(dragTarget.color);
			}
			blocks[blocks.indexOf(dragTarget)] = undefined;
			dragTarget.destroy();
			// Clean up undefined entries from blocks array
			for (var i = blocks.length - 1; i >= 0; i--) {
				if (blocks[i] === undefined) {
					blocks.splice(i, 1);
				}
			}
			if (blocks.length === 0) {
				game.createBlocks();
			}
			var pointsToAdd = board.checkLines();
			if (pointsToAdd) {
				score += Math.pow(pointsToAdd, 2) * 10;
				scoreTxt.setText(score);
			}
		}
		board.removeTint();
		dragTarget = undefined;
	}
});
game.createBlocks = function () {
	for (var i = 0; i < 3; i++) {
		game.createBlock(i);
	}
};
var score = 0;
game.createBlocks();
var scoreTxt = new Text2('0', {
	size: 150,
	fill: 0xFFFFFF,
	font: 'Impact',
	dropShadow: true,
	dropShadowColor: '#2a636e'
});
scoreTxt.anchor.set(.5, 0);
LK.gui.top.addChild(scoreTxt);
game.isMovePossible = function () {
	for (var a = 0; a < blocks.length; a++) {
		if (!blocks[a]) continue; // skip undefined entries
		for (var i = 0; i < 10; i++) {
			for (var j = 0; j < 10; j++) {
				if (board.grid[i][j].filled) {
					continue;
				}
				var canPlace = true;
				for (var k = 0; k < blocks[a].shape.length; k++) {
					for (var l = 0; l < blocks[a].shape[k].length; l++) {
						if (blocks[a].shape[k][l] === 1) {
							if (i + k < 0 || i + k >= 10 || j + l < 0 || j + l >= 10 || board.grid[i + k][j + l].filled) {
								canPlace = false;
								break;
							}
						}
					}
					if (!canPlace) {
						break;
					}
				}
				if (canPlace) {
					return true;
				}
			}
		}
	}
	return false;
};
var isGameOver = false;
LK.on('tick', function () {
	board.tick();
	if (isGameOver || !game.isMovePossible()) {
		LK.effects.flashScreen(0xffffff, 1000);
		scoreTxt.setText(score); // Ensure score is up to date
		LK.showGameOver();
	}
	for (var a = blocks.length - 1; a >= 0; a--) {
		if (blocks[a]) {
			if (blocks[a] != dragTarget) {
				blocks[a].moveTowardsHomePosition();
			} else {
				blocks[a].moveToDragTarget();
				// If block is dragged off screen, reset to start position
				if (blocks[a].x < 0 || blocks[a].x > 2048 || blocks[a].y < 0 || blocks[a].y > 2732) {
					blocks[a].x = blocks[a].startX;
					blocks[a].y = blocks[a].startY;
				}
			}
		}
	}
});

===================================================================
--- original.js
+++ change.js
@@ -377,10 +377,39 @@
 			this.blocks = [];
 			// 3. Recreate blocks with new shape
 			var blockSize = 160;
 			var background = this.children[0];
+			// Find the anchor cell (first '1' in the old shape)
+			var anchorI = 0,
+				anchorJ = 0;
+			var foundAnchor = false;
+			for (var i = 0; i < oldShape.length && !foundAnchor; i++) {
+				for (var j = 0; j < oldShape[i].length && !foundAnchor; j++) {
+					if (oldShape[i][j] === 1) {
+						anchorI = i;
+						anchorJ = j;
+						foundAnchor = true;
+					}
+				}
+			}
+			// After rotation, find the new anchor cell (first '1' in the new shape)
+			var newAnchorI = 0,
+				newAnchorJ = 0;
+			foundAnchor = false;
+			for (var i = 0; i < newShape.length && !foundAnchor; i++) {
+				for (var j = 0; j < newShape[i].length && !foundAnchor; j++) {
+					if (newShape[i][j] === 1) {
+						newAnchorI = i;
+						newAnchorJ = j;
+						foundAnchor = true;
+					}
+				}
+			}
+			// Calculate offset so that the anchor cell stays at the same place visually
 			var blockOffsetX = (background.width / 2 - this.shape[0].length * blockSize) / 2 - blockSize / 2;
 			var blockOffsetY = (background.height / 2 - this.shape.length * blockSize) / 2 - blockSize / 2;
+			var anchorDeltaX = (anchorJ - newAnchorJ) * blockSize;
+			var anchorDeltaY = (anchorI - newAnchorI) * blockSize;
 			for (var i = 0; i < this.shape.length; i++) {
 				for (var j = 0; j < this.shape[i].length; j++) {
 					if (this.shape[i][j] === 1) {
 						var blockAsset = this.attachAsset('block', {
@@ -389,10 +418,10 @@
 						});
 						blockAsset.tint = this.color;
 						blockAsset.width = blockSize;
 						blockAsset.height = blockSize;
-						blockAsset.x = j * blockSize + blockOffsetX;
-						blockAsset.y = i * blockSize + blockOffsetY;
+						blockAsset.x = j * blockSize + blockOffsetX + anchorDeltaX;
+						blockAsset.y = i * blockSize + blockOffsetY + anchorDeltaY;
 						this.blocks.push(blockAsset);
 						this.addChild(blockAsset);
 					}
 				}