* {margin: 0; padding: 0;}
html, body {height: 100%;}
body {background: #3f3f3f;}
ul {text-align: center; margin-top: 10em;}
ul li {display: inline;}
ul li a {display: inline-block; padding: 5px 10px; background: #000; color: #fff; line-height: 3}
ul li a:hover {background: #e4e4e4; color: #333;}