From http://groundwork.sidereel.com/mixins Transitions

transitions

@mixin transition($transition:all 0.2s) {
  -ms-transition:$transition; // IE10+
  -o-transition:$transition; // Opera
  -moz-transition:$transition; // Firefox
  -webkit-transition:$transition; // Webkit (Safari, Chrome, other)
  transition:$transition;
}