Edit in JSFiddle

<div class="flip-container">
    <div class="front-side">Front Side</div>
    <div class="back-side">Back Side</div>
</div>
<div class="flip-container">
    <div class="front-side">Front Side</div>
    <div class="back-side">Back Side</div>
</div>
<div class="flip-container">
    <div class="front-side">Front Side</div>
    <div class="back-side">Back Side</div>
</div>
<div class="flip-container">
    <div class="front-side">Front Side</div>
    <div class="back-side">Back Side</div>
</div>
<div class="flip-container">
    <div class="front-side">Front Side</div>
    <div class="back-side">Back Side</div>
</div>

* { box-sizing: border-box;}

.flip-container {
    float: left;
    position: relative;
    margin-right: 10px;
    margin-bottom: 10px;
    perspective: 1000px;
    -webkit-perspective: 1000px; 
}

.flip-container:lash-chid {
    margin-right: 0;
}

.flip-container,
.flip-container .front-side,
.flip-container .back-side {
    width: 180px;
    height: 150px;
}

.flip-container .front-side,
.flip-container .back-side {
    position: absolute;
    top: 0;
    left: 0;
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
    transition: 1.2s;
    -webkit-transition: 1.2s;
    color: #fff;
    font-size: 48px;
    text-align: center;
    padding-top: 20px;
}

.flip-container .back-side {
    background-color: #333;
    z-index: 1;
    transform: rotateY(180deg);
    -webkit-transform: rotateY(180deg);
}

.flip-container .front-side {
    background-color: #5d3696;
    z-index: 2;
    transform: rotateY(0deg);
    -webkit-transform: rotateY(0deg);
}

.flip-container:hover .front-side {
    transform: rotateY(-180deg);
    -webkit-transform: rotateY(-180deg);
}

.flip-container:hover .back-side {
    transform: rotateY(0deg);
    -webkit-transform: rotateY(0deg);
}