body {
	background-color: white;
	text-align: center;
	}

#box {
	top: 0; left: 0; width: 100%; height: 100%;
    position: fixed; display: table;
}

#center {
	width: 400px; height: auto;
	display: table-cell; vertical-align: middle; float: none;
}
	

img {display: block; margin: 1em auto}

a:link {background-image: url(images/enter_off.gif); text-decoration: none}
a:visited {background-image: url(images/enter_on.gif); text-decoration: none}
a:hover {background-image: url(images/enter_on.gif); text-decoration: none}
a:active {background-image: url(images/enter_on.gif); text-decoration: none}