#Centering Percentage Width/Height Elements | CSS-Tricks #http://css-tricks.com/centering-percentage-widthheight-elements/ translate() .center { position: absolute; left: 50%; top: 50%; /* Nope =( margin-left: -25%; margin-top: -25%; */ /* Yep! */ transform: translate(-50%, -50%); /* Not even necessary really. e.g. Height could be left out! */ width: 40%; height: 50%; } position:absolute; left: 30%; right:30%; top: 25%; bottom:25%; position: absolute; top: 0; right: 0; bottom: 0; left: 0; margin: auto; width: 40%; height: 50%; position:absolute; left: 30%; right:30%; top: 25%; bottom:25%;