.container{
margin:30px auto;
/* How pronounced should the 3D effects be */
perspective: 500;
-webkit-perspective: 500;
-moz-perspective: 500;
-ms-perspective: 500;
-o-perspective: 500;
width:150px;
height:150px;
position:relative;
/*Some UI */
border-radius:6px;
-webkit-border-radius:6px;
-moz-border-radius:6px;
-ms-border-radius:6px;
-o-border-radius:6px;
font-size:28px;
line-height:150px;
vertical-align:middle;
cursor:pointer;
}
.box-front,.box-back{
/* Enable 3D transforms */
transform-style: preserve-3d;
-webkit-transform-style: preserve-3d;
-moz-transform-style: preserve-3d;
-ms-transform-style: preserve-3d;
-o-transform-style: preserve-3d;
transform-style: preserve-3d;
backface-visibility: hidden;
-webkit-backface-visibility: hidden;
-moz-backface-visibility: hidden;
-ms-backface-visibility: hidden;
-o-backface-visibility: hidden;
width:100%;
height:100%;
position:absolute;
background-color:#0090d9;
/* Animate the transitions */
-webkit-transition:0.8s; text-align:center;
-moz-transition:0.8s; text-align:center;
-ms-transition:0.8s; text-align:center;
-o-transition:0.8s; text-align:center;
transition:0.8s; text-align:center;
color:#FFF;
border-radius:6px;
-webkit-border-radius:6px;
-moz-border-radius:6px;
-ms-border-radius:6px;
-o-border-radius:6px;
}
.box-back{
/* The back side is flipped 180 deg by default */
transform:rotateY(180deg);
-webkit-transform:rotateY(180deg);
-moz-transform:rotateY(180deg);
-ms-transform:rotateY(180deg);
-o-transform:rotateY(180deg);
background-color:#f35958;
}
.container:hover .box-front{
/* When the container is hovered, flip the front side and hide it .. */
transform:rotateY(180deg);
-webkit-transform:rotateY(180deg);
-moz-transform:rotateY(180deg);
-ms-transform:rotateY(180deg);
-o-transform:rotateY(180deg);
}
.container:hover .box-back{
/* .. at the same time flip the back side into visibility */
transform:rotateY(360deg);
-webkit-transform:rotateY(360deg);
-moz-transform:rotateY(360deg);
-ms-transform:rotateY(360deg);
-o-transform:rotateY(360deg);
}
<div class="container">
<div class="box-front">Front :)</div>
<div class="box-back">Back :D </div>
</div>