html{width: 100%; height: 100%;}
body{color: #fff; width: 100%; height: 100%; margin: 0;}
a{display: block; width: 250px; height: 250px; position: absolute; top: 50%; left: 50%; margin: -125px 0 0 -125px; background: transparent; border-radius: 300px; text-indent: -10000px}
body.notFound{background: #000 url(http://static.cdprojektred.com/common/404/404_error_en.jpg) 50% 50% no-repeat;}