modalBox would listen for updates to the content within the box and

attempt to update its size and position accordingly. These values could

end up being non-integers, causing elements to subtly jump.
To fix this, we just need to use Math.ceil() on the values to ensure

that we get whole numbers.

Saw this issue in a modalBox I had built. Some small updates would just

cause the box's contents to shift just a bit. That no longer happens

after this change.