Update index.html

index.html

@@ -289,7 +289,7 @@
                         keyElement.classList.add('black-key');
                         // Position black key centered over the "crack" of the preceding white key
                         // currentWhiteKeyVisualOffset is the right edge of the *previous* white key
-                        keyElement.style.left = (currentWhiteKeyVisualOffset - (BLACK_KEY_WIDTH_PX / 2) - (WHITE_KEY_OVERLAP_PX / 2) - 5) + 'px';
+                        keyElement.style.left = (currentWhiteKeyVisualOffset - (BLACK_KEY_WIDTH_PX / 2) - (WHITE_KEY_OVERLAP_PX / 2) + 9) + 'px';
                         keyElement.style.top = '0px';
                     } else { // White key
                         keyElement.classList.add('white-key');