@media only screen and (-webkit-min-device-pixel-ratio: 2), only screen and (min-device-pixel-ratio: 2) { .replace-2x { font-size: 1px; } .example { background-image: url(../images/example2x.png); -webkit-background-size:13px 13px; -moz-background-size:13px 13px; -o-background-size:13px 13px; background-size:13px 13px; } }