#btn_overmij a {
	margin: 0px; padding:0px 0px 0px 0px;
	background: url("../images/overmij.png") 0 0 no-repeat;
	text-decoration: none;
	display:block;
	position:absolute;
	left:150px;
	top:230px;
	width:180px;
	height:240px;
	}
#btn_overmij a:hover {	
	background-position: -180px 0;
	}
#btn_overmij a:active {
	background-position: -180px 0;
	}
	
#btn_portfolio a {
	margin: 0px; padding:0px 0px 0px 0px;
	background: url("../images/portfolio.png") 0 0 no-repeat;
	text-decoration: none;
	display:block;
	position:absolute;
	left:375px;
	top:230px;
	width:180px;
	height:240px;
	}
#btn_portfolio a:hover {	
	background-position: -180px 0;
	}
#btn_portfolio a:active {
	background-position: -180px 0;
	}
	
#btn_contact a {
	margin: 0px; padding:0px 0px 0px 0px;
	background: url("../images/contact.png") 0 0 no-repeat;
	text-decoration: none;
	display:block;
	position:absolute;
	left:600px;
	top:230px;
	width:180px;
	height:240px;
	}
#btn_contact a:hover {	
	background-position: -180px 0;
	}
#btn_contact a:active {
	background-position: -180px 0;
	}