CSS: Hover a HTML submit button

Question

I'm trying to style a HTML submit button in CSS:

HTML:

<input type="submit" value="Yes" id="popUpYes">

CSS:

#popUpYes
{
  width: 60px;
  height: 30px;
  background-color: black;
}
#popUpYes:hover
{
  background-color: white;
}

The basic style works but the background does not change color on hover.

Answer 1

Your original code works for me. Be sure you don't have any other conflicting styles inherited by the submit button.