body {
    font-size: 0;
}
.flip {
    display: inline-block;
    margin: 5px;
    position: relative;
    width: 40px;
    -webkit-perspective: 100;
}
.faces {
    height: 100%;
    position: relative;
    -webkit-transform-style: flat;
    -webkit-transition: .25s 1s ease-in-out;
}
.faces div {
    height: 30px;
    -webkit-backface-visibility: hidden;
}
.front {
    background: #f66;
}
.back {
    background: #6cf;
    bottom: 0;
    left: 0;
    position: absolute;
    right: 0;
    top: 0;
    -webkit-transform: rotateY(-180deg);
}
.flip:hover .faces {
    -webkit-transform: rotateY(-180deg);
    -webkit-transition: 0s ease-in-out;
}
​