Copie e cole o código abaixo:
@media (min-width:981px){
.flip-box-row {
background-color: transparent;
width: 250px;
height: 250px;
-webkit-perspective: 1000px;
perspective: 1000px;
}

.flip-box-column {
position: relative;
width:100%;
height: 100%;
-webkit-transition: transform 0.8s;
transition: transform 0.8s;
-webkit-transform-style: preserve-3d;
transform-style: preserve-3d;
}

.flip-box-row:hover .flip-box-column {
-webkit-transform: rotateY(180deg);
transform: rotateY(180deg);
}

.flip-box-front, .flip-box-back{
position: absolute;
width:100%;
height: 100%;
-webkit-transform: translate3d(0,0,0);
-webkit-backface-visibility: hidden;
backface-visibility: hidden;
}

.flip-box-back {
-webkit-transform: rotateY(180deg);
transform: rotateY(180deg);
}
}