a#yes,
a#no {
	display: block;
	height: 25px;
	width: 157px;
}

a#yes {
	background: transparent url(http://asset1.my-next-home.de/images/immotipp/yes.gif);
	
}

a#no {
	background: transparent url(http://asset1.my-next-home.de/images/immotipp/no.gif);
	
}

a#yes:hover,
a#no:hover {
	background-position: -157px 0;
}