patternfly/components/bootstrap/less/mixins/opacity.less

This reference implementation of PatternFly is based on [Bootstrap v3](http://getbootstrap.com/). Think of PatternFly as a "skinned" version of Bootstrap with additional components and customizations.

// Opacity

.opacity(@opacity) {
  opacity: @opacity;
  // IE8 filter
  @opacity-ie: (@opacity * 100);
  filter: ~"alpha(opacity=@{opacity-ie})";
}