I did some googling and here\'s my answer
to mirror use transform: scaleX(-1);
to flip use rotate(180deg);
Your code is correct but there is an easier way to do this:
img.flip {
-moz-transform: scaleX(-1); /* Gecko */
-o-transform: scaleX(-1); /* Opera */
-webkit-transform: scaleX(-1); /* Webkit */
transform: scaleX(-1); /* Standard */
filter: FlipH; /* IE 6/7/8 */
}
I think this solves your centered mirroring issue.
As noted you will have to set the element to use a display of block, inline-block etc.