You can flip both vertical and horizontal at the same time
-moz-transform: scaleX(-1) scaleY(-1);
-o-transform: scaleX(-1) scaleY(-1);
-webkit-transform: scaleX(-1) scaleY(-1);
transform: scaleX(-1) scaleY(-1);
And with the transition property you can get a cool flip
-webkit-transition: transform .4s ease-out 0ms;
-moz-transition: transform .4s ease-out 0ms;
-o-transition: transform .4s ease-out 0ms;
transition: transform .4s ease-out 0ms;
transition-property: transform;
transition-duration: .4s;
transition-timing-function: ease-out;
transition-delay: 0ms;
Actually it flips the whole element, not just the background-image
SNIPPET
function flip(){_x000D_
var myDiv = document.getElementById('myDiv');_x000D_
if (myDiv.className == 'myFlipedDiv'){_x000D_
myDiv.className = '';_x000D_
}else{_x000D_
myDiv.className = 'myFlipedDiv';_x000D_
}_x000D_
}
_x000D_
#myDiv{_x000D_
display:inline-block;_x000D_
width:200px;_x000D_
height:20px;_x000D_
padding:90px;_x000D_
background-color:red;_x000D_
text-align:center;_x000D_
-webkit-transition:transform .4s ease-out 0ms;_x000D_
-moz-transition:transform .4s ease-out 0ms;_x000D_
-o-transition:transform .4s ease-out 0ms;_x000D_
transition:transform .4s ease-out 0ms;_x000D_
transition-property:transform;_x000D_
transition-duration:.4s;_x000D_
transition-timing-function:ease-out;_x000D_
transition-delay:0ms;_x000D_
}_x000D_
.myFlipedDiv{_x000D_
-moz-transform:scaleX(-1) scaleY(-1);_x000D_
-o-transform:scaleX(-1) scaleY(-1);_x000D_
-webkit-transform:scaleX(-1) scaleY(-1);_x000D_
transform:scaleX(-1) scaleY(-1);_x000D_
}
_x000D_
<div id="myDiv">Some content here</div>_x000D_
_x000D_
<button onclick="flip()">Click to flip</button>
_x000D_