Font-Awesome/src/assets/font-awesome/scss/_extras.scss

/* EXTRAS
 * -------------------------- */

/* Stacked and layered icon */
@include icon-stack;

/* Animated rotating icon */
.icon-spin {
  display: inline-block;
  @include animation(spin 2s infinite linear);
}

@-moz-keyframes spin {
  0% {
    -moz-transform: rotate(0deg);
  }
  100% {
    -moz-transform: rotate(359deg);
  }
}


@-webkit-keyframes spin {
  0% {
    -webkit-transform: rotate(0deg);
  }
  100% {
    -webkit-transform: rotate(359deg);
  }
}


@-o-keyframes spin {
  0% {
    -o-transform: rotate(0deg);
  }
  100% {
    -o-transform: rotate(359deg);
  }
}


@-ms-keyframes spin {
  0% {
    -ms-transform: rotate(0deg);
  }
  100% {
    -ms-transform: rotate(359deg);
  }
}


@keyframes spin {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(359deg);
  }
}


/* Icon rotations and mirroring */

.icon-rotate-90:before {
  @include transform(rotate(90deg));
  filter: progid:DXImageTransform.Microsoft.BasicImage(rotation=1);
}

.icon-rotate-180:before {
  @include transform(rotate(180deg));
  filter: progid:DXImageTransform.Microsoft.BasicImage(rotation=2);
}

.icon-rotate-270:before {
  @include transform(rotate(270deg));
  filter: progid:DXImageTransform.Microsoft.BasicImage(rotation=3);
}

.icon-flip-horizontal:before {
  @include transform(scale(-1, 1));
}

.icon-flip-vertical:before {
  @include transform(scale(1, -1));
}