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t/sass-spec/spec/libsass-todo-issues/issue_931/input.scss  view on Meta::CPAN

@mixin img-opacity($trans) {
          filter : alpha(opacity=($trans * 100));
      -ms-filter : "progid:DXImageTransform.Microsoft.Alpha(Opacity=#{$trans * 100})";
    -moz-opacity : $trans;
  -khtml-opacity : $trans;
         opacity : $trans;
}

img {
  @include img-opacity(.5);
}