autogenerating IE-fallback mediaquery mixin

mediaqueries.scss

// ----
// Sass (v3.4.9)
// Compass (v1.0.1)
//
// a combination of the z-index property map Gist: http://sassmeister.com/gist/29202828a1c37714f5e1
// and Jake Archibald's IE-friendly Sass mediaqueries: http://jakearchibald.github.io/sass-ie/
// thanks to both for their respective contributions.
//
// this variation uses named breakpoints taken from a map, rather than using hardcoded values within
// the mixin call. removes the need for hardcoded arbitrary values within code.
//
// usage: @include respond-to(name-of-breakpoint, breakpoint-type, breakpoint-map) { @content; }
//
// 'breakpoint-type' defaults to 'default' unless specified, and if specified,
// 'breakpoint-map' (usually $breakpoints) needs to be called, too.
//
// setup an IE-based stylesheet as per Jake's instructions to create an autogenerated, mediaquery-less
// fallback stylesheet which can be included in HTML via IE conditionals.
// ----

$fix-mqs: false !default;

$breakpoints: (
  default: (
    mobile-skinny: 20em,
    mobile-wide: 30em,
    tablet: 45em,
    desktop: 60em,
    superwide: 67.5em
  )
);

@mixin respond-to($width, $type: default, $array: $breakpoints) {
  @if map-has-key($breakpoints, $type) {
    @if map-has-key(map-get($breakpoints, $type), $width) {
      @if $fix-mqs {
        @if $fix-mqs >= map-get(map-get($breakpoints, $type), $width) {
          @content;
        }
      } @else {
        @media screen and (min-width: map-get(map-get($breakpoints, $type), $width)) {
          @content;
        }
      }
    } @else {
      @warn 'There is no element "#{$name}" in the widths map.'
    }
  } @else {
    @warn 'The desired type "#{$type}" is not available, please add it to the map of specify another.'
  }
}

$old-ie: false !default;

@mixin old-ie {
	@if $old-ie {
		@content;
	}
}

//$fix-mqs: 80em;
//$old-ie: true;

body {
  @include respond-to(superwide) {
    background-color: #bada55;
  }
  
  @include old-ie {
    zoom: 1;
  }
}

output.css

@media screen and (min-width: 67.5em) {
  body {
    background-color: #bada55;
  }
}