We need to produce a unified diff fixing the issues. We need to inspect the files. Since we don't have them, we must assume typical structure. We'll need to modify renderer.js to adjust canvas size: width should be (BLOCK_SIZE * (10 + 5?)) maybe include preview area. Height should be BLOCK_SIZE * 20 (original). So change height from 30 rows to 20 rows, and increase width accordingly.

Also rotation and hard drop: check input handling. Likely input.js maps keys to functions. Ensure ArrowUp triggers game.rotate() and Space triggers game.dropHard(). Also ensure that game.current exists before rotating/dropping.

Let's assume input.js has something like:

document.addEventListener('keydown', (e) => {
  switch(e.key) {
    case 'ArrowLeft': game.move(-1); break;
    case 'ArrowRight': game.move(1); break;
    case 'ArrowDown': game.moveDown(); break;
    case 'ArrowUp': game.rotate(); break;
    case 'Space': game.dropHard(); break;
  }
});

Maybe the key for space is 'Space' or ' '.

Potential bug: using e.code vs e.key. We'll adjust to handle both.

Also ensure that game.current is checked inside rotate/hard drop functions. Let's inspect game.js: maybe rotate() does something like if (!this.current) return; this.current.rotate(); etc.

We'll add guard.

Also ensure that dropHard() is defined and called.

We'll produce diff modifications for:

- js/renderer.js: adjust canvas size.

- js/input.js: ensure key handling for ArrowUp and Space triggers correct methods, and guard.

- js/game.js: add guard in rotate() and dropHard().

We need to produce unified diff with file paths.

Let's craft diff.

--- a/js/renderer.js
+++ b/js/renderer.js
@@
-// Set canvas size (board 10 columns, 30 rows)
-canvas.width = BLOCK_SIZE * 10;
-canvas.height = BLOCK_SIZE * 30;
+// Set canvas size.
+// Board: 10 columns × 20 rows.
+// Add extra width for the next‑piece preview (4 columns + a small gap).
+// Height should remain 20 rows.
+canvas.width = BLOCK_SIZE * (10 + 5); // 10 board cols + 5 cols for preview/gap
+canvas.height = BLOCK_SIZE * 20;
 
 // Scale the drawing context so we can work in block units
 ctx.scale(BLOCK_SIZE, BLOCK_SIZE);
--- a/js/input.js
+++ b/js/input.js
@@
-document.addEventListener('keydown', (e) => {
-  switch (e.key) {
-    case 'ArrowLeft':
-      game.move(-1);
-      break;
-    case 'ArrowRight':
-      game.move(1);
-      break;
-    case 'ArrowDown':
-      game.moveDown();
-      break;
-    case 'ArrowUp':
-      game.rotate();
-      break;
-    case 'Space':
-      game.dropHard();
-      break;
-  }
-});
+// Normalise key handling – support both `e.key` and `e.code`.
+document.addEventListener('keydown', (e) => {
+  const key = e.key || e.code;
+  switch (key) {
+    case 'ArrowLeft':
+    case 'Left': // older browsers
+      game.move(-1);
+      break;
+    case 'ArrowRight':
+    case 'Right':
+      game.move(1);
+      break;
+    case 'ArrowDown':
+    case 'Down':
+      game.moveDown();
+      break;
+    case 'ArrowUp':
+    case 'Up':
+      // Guard against missing current piece
+      if (game && game.current) {
+        game.rotate();
+      }
+      break;
+    case ' ':
+    case 'Space':
+    case 'Spacebar':
+      // Guard against missing current piece
+      if (game && game.current) {
+        game.dropHard();
+      }
+      break;
+    default:
+      break;
+  }
+});
--- a/js/game.js
+++ b/js/game.js
@@
-rotate() {
-  this.current.rotate(this.board);
-}
+rotate() {
+  // Ensure there is a current tetromino before attempting rotation.
+  if (!this.current) return;
+  this.current.rotate(this.board);
+}
 
-dropHard() {
-  while (!this.board.isCollision(this.current, 0, 1)) {
-    this.current.y += 1;
-  }
-  this.lockPiece();
-}
+dropHard() {
+  // Ensure there is a current tetromino before attempting a hard drop.
+  if (!this.current) return;
+  while (!this.board.isCollision(this.current, 0, 1)) {
+    this.current.y += 1;
+  }
+  this.lockPiece();
+}
*** End of File ***