For whatever reason I am really beating myself up with this... No doubt because of the lack of support for a real \"proper\" way of vertically centering anything.
If I understand your issue correctly, this may work for you:
Working Demo
If you need the image to scale when hovered over, then simply adding a :hover on the container and changing it's width should work.
CSS:
.container {
// existing styles
-webkit-transition: all .2s; // needs prefixes for other browsers.
}
.container:hover {
width: 500px;
}
The only issue is that transition has no support for IE9 or earlier. So you'd need to go a JS route if that is an issue.