/**
 * Drop shadow w/ perspective
 *
 * @thanks Nicolas Gallagher @necolas
 * @link http://nicolasgallagher.com/css-drop-shadows-without-images/demo/
 */
@mixin drop-shadow-perspective($skew: 50deg, $distance-x: 80px, $distance-y: 5px, $box-shadow-radius: 8px, $color: rgba(#000, .4))
{
    position: relative;

    &:before
    {
        content:"";
        position:absolute;
        z-index:-2;

        left: $distance-x;
        bottom: $distance-y;
        width: 50%;
        height: 35%;

        @include box-shadow(-$distance-x 0 $box-shadow-radius $color);
        @include transform(skew($skew));
        @include transform-origin(0 100%);
    }
}