@mixin clearfix() {
  &:before,
  &:after {
    content: " "; /* 1 */
    display: table; /* 2 */
  }
  &:after {
    clear: both;
  }
}

// Webkit-style focus
@mixin tab-focus() {
  // Default
  outline: thin dotted #000;
  outline-offset: -2px;
}

// Center-align a block level element
@mixin center-block() {
  display: block;
  margin-left: auto;
  margin-right: auto;
}

// Sizing shortcuts
@mixin size($width, $height) {
  width: $width;
  height: $height;
}

@mixin square($size) {
  @include size($size, $size);
}

@mixin flexbox() {
  display: flex;
}

@mixin flex-inline() {
  display: inline-flex;
}

@mixin align-items($argument) {
  align-items: $argument;
}

@mixin flex-column {
  flex-direction: column;
}

@mixin flex-row {
  flex-direction: row;
}

// Placeholder text
@mixin placeholder($color: $input-color-placeholder) {
  &.placeholder {
    color: $color;
  }
}

// Placeholder text
@mixin selected($color, $background) {
  &::selection {
    background: $background; /* Safari */
    color: $color;
  }
}

@mixin placeholder-height($height) {
  &.placeholder {
    line-height: $height;
  }
}

// Text overflow
// Requires inline-block or block for proper styling
@mixin text-overflow() {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

// CSS image replacement
@mixin text-hide() {
  font: 0/0 a;
  color: transparent;
  text-shadow: none;
  background-color: transparent;
  border: 0;
}

@mixin invisible() {
  visibility: hidden;
}

//Padding Helper Classes
@mixin generate-paddings-options-prefix($prefix,$n, $j: 0) {
  @if $j <= $n {
    @for $i from $j through $n {
      $step: $i*5;
      .#{$prefix}-p-t-#{$step} {
        margin-top: ($step*1px) !important;
      }
      .#{$prefix}-p-r-#{$step} {
        margin-right: ($step*1px) !important;
      }
      .#{$prefix}-p-l-#{$step} {
        margin-left: ($step*1px) !important;
      }
      .#{$prefix}-p-b-#{$step} {
        margin-bottom: ($step*1px) !important;
      }
      //@include generate-margin-options($n, ($i + 1));
    }
  }
}

//Margins Helper Classes
@mixin generate-margin-options-prefix($prefix,$n, $j: 0) {
  @if $j <= $n {
    @for $i from $j through $n {
      $step: $i*5;
      .#{$prefix}-m-t-#{$step} {
        margin-top: ($step*1px) !important;
      }
      .#{$prefix}-m-r-#{$step} {
        margin-right: ($step*1px) !important;
      }
      .#{$prefix}-m-l-#{$step} {
        margin-left: ($step*1px) !important;
      }
      .#{$prefix}-m-b-#{$step} {
        margin-bottom: ($step*1px) !important;
      }
      //@include generate-margin-options($n, ($i + 1));
    }
  }
}

// CSS3 PROPERTIES
// --------------------------------------------------
@mixin mask($arguments) {
  mask: $arguments;
}

@mixin box_scale($scale) {
  transform: scale($scale);
}

// Single side border-radius
@mixin border-top-radius($radius) {
  border-top-right-radius: $radius;
  border-top-left-radius: $radius;
}

@mixin border-right-radius($radius) {
  border-bottom-right-radius: $radius;
  border-top-right-radius: $radius;
}

@mixin border-bottom-radius($radius) {
  border-bottom-right-radius: $radius;
  border-bottom-left-radius: $radius;
}

@mixin border-left-radius($radius) {
  border-bottom-left-radius: $radius;
  border-top-left-radius: $radius;
}

@mixin border-radius($radius) {
  border-radius: $radius;
}

// Drop shadows
@mixin box-shadow($shadow) {
  box-shadow: $shadow;
}

@mixin animation($properties) {
  animation: $properties;
}

// Transitions
@mixin transition($transition) {
  transition: $transition;
}

@mixin transition-property($transition-property) {
  transition-property: $transition-property;
}

@mixin transition-delay($transition-delay) {
  transition-delay: $transition-delay;
}

@mixin transition-duration($transition-duration) {
  transition-duration: $transition-duration;
}

@mixin transition-transform($transition) {
  transition: transform $transition;
}

// Transformations
@mixin rotate($degrees) {
  transform: rotate($degrees);
}

@mixin scale($ratio) {
  transform: scale($ratio);
}

@mixin translate($x, $y) {
  transform: translate($x, $y);
}

@mixin translateY($y) {
  transform: translateY($y);
}

@mixin translateX($x) {
  transform: translateX($x);
}

@mixin skew($x, $y) {
  transform: skew($x, $y);
}

@mixin translate3d($x, $y, $z) {
  transform: translate3d($x, $y, $z);
}

@mixin rotateX($degrees) {
  transform: rotateX($degrees);
}

@mixin rotateY($degrees) {
  transform: rotateY($degrees);
}

@mixin perspective($perspective) {
  perspective: $perspective;
}

@mixin perspective-origin($perspective) {
  perspective-origin: $perspective;
}

@mixin transform-origin($origin) {
  transform-origin: $origin;
}

@mixin transform-style($style) {
  transform-style: $style;
}

// Backface visibility
// Prevent browsers from flickering when using CSS 3D transforms.
// Default value is `visible`, but can be changed to `hidden`
// See git pull https://github.com/dannykeane/bootstrap.git backface-visibility for examples
@mixin backface-visibility($visibility) {
  backface-visibility: $visibility;
}

// Background clip
@mixin background-clip($clip: border-box) {
  background-clip: $clip;
}

// Box sizing
@mixin box-sizing($boxmodel) {
  box-sizing: $boxmodel;
}

// User select
// For selecting text on the page
@mixin user-select($select) {
  user-select: $select;
}

// Resize anything
@mixin resizable($direction) {
  resize: $direction; // Options: horizontal, vertical, both
  overflow: auto; // Safari fix
}

// CSS3 Content Columns
@mixin content-columns($column-count, $column-gap: $grid-gutter-width) {
  column-count: $column-count;
  column-gap: $column-gap;
}

// Optional hyphenation
@mixin hyphens($mode: auto) {
  word-wrap: break-word;
  hyphens: $mode;
}

// Opacity
@mixin opacity($opacity) {
  opacity: $opacity;
  // IE8 filter
  $opacity-ie: ($opacity * 100);
  filter: alpha(opacity=$opacity-ie);
}

// GRADIENTS
// --------------------------------------------------
@mixin linear-gradient($from, $to) {
  background: $to;
  background: linear-gradient(to bottom, $from 0%, $to 100%);
  filter: progid:DXImageTransform.Microsoft.gradient(GradientType=0, startColorstr=#{$from}, endColorstr=#{$to})
}

#gradient {
  // Horizontal gradient, from left to right
  //
  // Creates two color stops, start and end, by specifying a color and position for each color stop.
  // Color stops are not available in IE9 and below.
  @mixin horizontal($start-color: #555, $end-color: #333, $start-percent: 0%, $end-percent: 100%) {
    // Standard, IE10
    background: linear-gradient(to right, $start-color $start-percent, $end-color $end-percent) repeat-x;
    filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#{ie-hex-str($start-color)}', endColorstr='#{ie-hex-str($end-color)}', GradientType=1); // IE9 and down
  }
  // Vertical gradient, from top to bottom
  //
  // Creates two color stops, start and end, by specifying a color and position for each color stop.
  // Color stops are not available in IE9 and below.
  @mixin vertical($start-color: #555, $end-color: #333, $start-percent: 0%, $end-percent: 100%) {
    // Standard, IE10
    background: linear-gradient(to bottom, $start-color $start-percent, $end-color $end-percent) repeat-x;
    filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#{ie-hex-str($start-color)}', endColorstr='#{ie-hex-str($end-color)}', GradientType=0); // IE9 and down
  }
  @mixin directional($start-color: #555, $end-color: #333, $deg: 45deg) {
    // Standard, IE10
    background: linear-gradient($deg, $start-color, $end-color) repeat-x;
  }
  @mixin horizontal-three-colors($start-color: #00b3ee, $mid-color: #7a43b6, $color-stop: 50%, $end-color: #c3325f) {
    background: linear-gradient(to right, $start-color, $mid-color $color-stop, $end-color) no-repeat;
    filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#{ie-hex-str($start-color)}', endColorstr='#{ie-hex-str($end-color)}', GradientType=1); // IE9 and down, gets no color-stop at all for proper fallback
  }
  @mixin vertical-three-colors($start-color: #00b3ee, $mid-color: #7a43b6, $color-stop: 50%, $end-color: #c3325f) {
    background: linear-gradient($start-color, $mid-color $color-stop, $end-color) no-repeat;
    filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#{ie-hex-str($start-color)}', endColorstr='#{ie-hex-str($end-color)}', GradientType=0); // IE9 and down, gets no color-stop at all for proper fallback
  }
  @mixin radial($inner-color: #555, $outer-color: #333) {
    background: radial-gradient(circle, $inner-color, $outer-color) no-repeat;
  }
  @mixin striped($color: rgba(255,255,255,.15), $angle: 45deg) {
    background-image: linear-gradient($angle, $color 25%, transparent 25%, transparent 50%, $color 50%, $color 75%, transparent 75%, transparent);
  }
}

// Reset filters for IE
//
// When you need to remove a gradient background, do not forget to use this to reset
// the IE filter for IE9 and below.
@mixin reset-filter() {
  filter: progid:DXImageTransform.Microsoft.gradient(enabled = false);
}

// Retina images
//
// Short retina mixin for setting background-image and -size
@mixin img-retina($file-1x, $file-2x, $width-1x, $height-1x) {
  background-image: url("${file-1x}");
  @media only screen and (min-device-pixel-ratio: 2),
  only screen and (min-resolution: 192dpi),
  only screen and (min-resolution: 2dppx) {
    background-image: url("${file-2x}");
    background-size: $width-1x $height-1x;
  }
}

// Responsive image
//
// Keep images from scaling beyond the width of their parents.
@mixin img-responsive($display: block) {
  display: $display;
  max-width: 100%; // Part 1: Set a maximum relative to the parent
  height: auto; // Part 2: Scale the height according to the width, otherwise you get stretching
}

@mixin keyframe ($animation_name) {
  @-webkit-keyframes #{$animation_name} {
    @content;
  }

  @-moz-keyframes #{$animation_name} {
    @content;
  }

  @-o-keyframes #{$animation_name} {
    @content;
  }

  @keyframes #{$animation_name} {
    @content;
  }
}

// Import the Compass Plugin
//--------------------------------
// Normal
//--------------------------------
@function blend-normal ($foreground, $background) {
  $opacity: opacity($foreground);
  $background-opacity: opacity($background);
  // calculate opacity
  $bm-red: red($foreground) * $opacity + red($background) * $background-opacity * (1 - $opacity);
  $bm-green: green($foreground) * $opacity + green($background) * $background-opacity * (1 - $opacity);
  $bm-blue: blue($foreground) * $opacity + blue($background) * $background-opacity * (1 - $opacity);
  @return rgb($bm-red, $bm-green, $bm-blue);
}

//--------------------------------
// Multiply
//--------------------------------
@function blend-multiply ($foreground, $background) {
  $bm-red: red($background) * red($foreground) / 255;
  $bm-green: green($background) * green($foreground) / 255;
  $bm-blue: blue($background) * blue($foreground) / 255;
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

//--------------------------------
// Lighten
//--------------------------------
@function blend-lighten ($foreground, $background) {
  $bm-red: blend-lighten-color(red($foreground), red($background));
  $bm-green: blend-lighten-color(green($foreground), green($background));
  $bm-blue: blend-lighten-color(blue($foreground), blue($background));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

@function blend-lighten-color($foreground, $background) {
  @if $background > $foreground {
    $foreground: $background;
  }
  @return $foreground;
}

//--------------------------------
// Darken
//--------------------------------
@function blend-darken ($foreground, $background) {
  $bm-red: blend-darken-color(red($foreground), red($background));
  $bm-green: blend-darken-color(green($foreground), green($background));
  $bm-blue: blend-darken-color(blue($foreground), blue($background));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

@function blend-darken-color($foreground, $background) {
  @if $background < $foreground {
    $foreground: $background;
  }
  @return $foreground;
}

//--------------------------------
// Darker Color
//--------------------------------
@function blend-darkercolor ($foreground, $background) {
  $bm-red: red($foreground);
  $bm-green: green($foreground);
  $bm-blue: blue($foreground);
  $background-red: red($background);
  $background-green: green($background);
  $background-blue: blue($background);
  @if $background-red * 0.3 + $background-green * 0.59 + $background-blue * 0.11 <= $bm-red * 0.3 + $bm-green * 0.59 + $bm-blue * 0.11 {
    $bm-red: $background-red;
    $bm-green: $background-green;
    $bm-blue: $background-blue;
  }
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

//--------------------------------
// Lighter Color
//--------------------------------
@function blend-lightercolor ($foreground, $background) {
  $bm-red: red($foreground);
  $bm-green: green($foreground);
  $bm-blue: blue($foreground);
  $background-red: red($background);
  $background-green: green($background);
  $background-blue: blue($background);
  @if $background-red * 0.3 + $background-green * 0.59 + $background-blue * 0.11 > $bm-red * 0.3 + $bm-green * 0.59 + $bm-blue * 0.11 {
    $bm-red: $background-red;
    $bm-green: $background-green;
    $bm-blue: $background-blue;
  }
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

//--------------------------------
// Linear Dodge
//--------------------------------
@function blend-lineardodge ($foreground, $background) {
  $bm-red: blend-lineardodge-color(red($foreground), red($background));
  $bm-green: blend-lineardodge-color(green($foreground), green($background));
  $bm-blue: blend-lineardodge-color(blue($foreground), blue($background));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

@function blend-lineardodge-color($foreground, $background) {
  @if $background + $foreground > 255 {
    $foreground: 255;
  } @else {
    $foreground: $background + $foreground;
  }
  @return $foreground;
}

//--------------------------------
// Linear Burn
//--------------------------------
@function blend-linearburn ($foreground, $background) {
  $bm-red: blend-linearburn-color(red($foreground), red($background));
  $bm-green: blend-linearburn-color(green($foreground), green($background));
  $bm-blue: blend-linearburn-color(blue($foreground), blue($background));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

@function blend-linearburn-color($foreground, $background) {
  @if $background + $foreground < 255 {
    $foreground: 0;
  } @else {
    $foreground: $background + $foreground - 255;
  }
  @return $foreground;
}

//--------------------------------
// Difference
//--------------------------------
@function blend-difference ($foreground, $background) {
  $bm-red: abs(red($background) - red($foreground));
  $bm-green: abs(green($background) - green($foreground));
  $bm-blue: abs(blue($background) - blue($foreground));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

//--------------------------------
// Screen
//--------------------------------
@function blend-screen ($foreground, $background) {
  $bm-red: blend-screen-color(red($foreground), red($background));
  $bm-green: blend-screen-color(green($foreground), green($background));
  $bm-blue: blend-screen-color(blue($foreground), blue($background));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

@function blend-screen-color($foreground, $background) {
  @return (255 - ( ( (255 - $foreground) * (255 - $background)) / 256));
}

//--------------------------------
// Exclusion
//--------------------------------
@function blend-exclusion ($foreground, $background) {
  $bm-red: blend-exclusion-color(red($foreground), red($background));
  $bm-green: blend-exclusion-color(green($foreground), green($background));
  $bm-blue: blend-exclusion-color(blue($foreground), blue($background));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

@function blend-exclusion-color($foreground, $background) {
  @return $background - ($background * (2 / 255) - 1) * $foreground;
}

//--------------------------------
// Overlay
//--------------------------------
@function blend-overlay ($foreground, $background) {
  $bm-red: blend-overlay-color(red($foreground), red($background));
  $bm-green: blend-overlay-color(green($foreground), green($background));
  $bm-blue: blend-overlay-color(blue($foreground), blue($background));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

@function blend-overlay-color($foreground, $background) {
  @if $background <= 255 / 2 {
    $foreground: (2 * $background * $foreground) / 255;
  } @else {
    $foreground: 255 - (255 - 2 * ($background - (255 / 2))) * (255 - $foreground) / 255;
  }
  @return $foreground;
}

//--------------------------------
// Soft Light
//--------------------------------
@function blend-softlight ($foreground, $background) {
  $bm-red: blend-softlight-color(red($foreground), red($background));
  $bm-green: blend-softlight-color(green($foreground), green($background));
  $bm-blue: blend-softlight-color(blue($foreground), blue($background));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

@function blend-softlight-color($foreground, $background) {
  @if $background < 128 {
    $foreground: (($foreground / 2) + 64) * $background * (2 / 255);
  } @else {
    $foreground: 255 - (191 - ($foreground / 2)) * (255 - $background) * (2 / 255);
  }
  @return $foreground;
}

//--------------------------------
// Hard Light
//--------------------------------
@function blend-hardlight ($foreground, $background) {
  $bm-red: blend-hardlight-color(red($foreground), red($background));
  $bm-green: blend-hardlight-color(green($foreground), green($background));
  $bm-blue: blend-hardlight-color(blue($foreground), blue($background));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

@function blend-hardlight-color($foreground, $background) {
  $tmp-blend: $foreground;
  @if $tmp-blend < 128 {
    $foreground: $background * $tmp-blend * (2 / 255);
  } @else {
    $foreground: 255 - (255-$background) * (255-$tmp-blend) * (2 / 255);
  }
  @return $foreground;
}

//--------------------------------
// Color Dodge
//--------------------------------
@function blend-colordodge ($foreground, $background) {
  $bm-red: blend-colordodge-color(red($foreground), red($background));
  $bm-green: blend-colordodge-color(green($foreground), green($background));
  $bm-blue: blend-colordodge-color(blue($foreground), blue($background));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

@function blend-colordodge-color($foreground, $background) {
  $tmp: $background * 256 / (255 - $foreground);
  @if $tmp > 255 or $foreground == 255 {
    $foreground: 255;
  } @else {
    $foreground: $tmp;
  }
  @return $foreground;
}

//--------------------------------
// Color Burn
//--------------------------------
@function blend-colorburn ($foreground, $background) {
  $bm-red: blend-colorburn-color(red($foreground), red($background));
  $bm-green: blend-colorburn-color(green($foreground), green($background));
  $bm-blue: blend-colorburn-color(blue($foreground), blue($background));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

@function blend-colorburn-color($foreground, $background) {
  $tmp: (255 - ((255 - $background) * 255) / $foreground);
  // TODO: hacked to replicate photoshop
  @if $foreground == 0 {
    $foreground: 255;
  } @else if $tmp < 0 {
    $foreground: 0;
  } @else {
    $foreground: $tmp;
  }
  @return $foreground;
}

//--------------------------------
// Linear Light
//--------------------------------
@function blend-linearlight ($foreground, $background) {
  $bm-red: blend-linearlight-color(red($foreground), red($background));
  $bm-green: blend-linearlight-color(green($foreground), green($background));
  $bm-blue: blend-linearlight-color(blue($foreground), blue($background));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

@function blend-linearlight-color($foreground, $background) {
  @if $foreground < 128 {
    $foreground: blend-linearburn-color($background, 2 * $foreground);
  } @else {
    $foreground: blend-lineardodge-color($background, 2 * ($foreground - 128));
  }
  @return $foreground;
}

//--------------------------------
// Vivid Light
//--------------------------------
@function blend-vividlight ($foreground, $background) {
  $bm-red: blend-vividlight-color(red($foreground), red($background));
  $bm-green: blend-vividlight-color(green($foreground), green($background));
  $bm-blue: blend-vividlight-color(blue($foreground), blue($background));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

@function blend-vividlight-color($foreground, $background) {
  @if $foreground < 128 {
    $foreground: blend-colorburn-color(2 * $foreground, $background);
  } @else {
    $foreground: blend-colordodge-color(2 * ($foreground - 128), $background);
  }
  @return $foreground;
}

//--------------------------------
// Pin Light
//--------------------------------
@function blend-pinlight ($foreground, $background) {
  $bm-red: blend-pinlight-color(red($foreground), red($background));
  $bm-green: blend-pinlight-color(green($foreground), green($background));
  $bm-blue: blend-pinlight-color(blue($foreground), blue($background));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

@function blend-pinlight-color($foreground, $background) {
  @if $foreground < 128 {
    $foreground: blend-darken-color($background, 2 * $foreground);
  } @else {
    $foreground: blend-lighten-color($background, 2 * ($foreground - 128));
  }
  @return $foreground;
}

//--------------------------------
// Hard Mix
//--------------------------------
@function blend-hardmix ($foreground, $background) {
  $bm-red: blend-hardmix-color(red($foreground), red($background));
  $bm-green: blend-hardmix-color(green($foreground), green($background));
  $bm-blue: blend-hardmix-color(blue($foreground), blue($background));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

@function blend-hardmix-color($foreground, $background) {
  $tmp: blend-vividlight-color($foreground, $background);
  @if $tmp < 128 {
    $foreground: 0;
  } @else {
    $foreground: 255;
  }
  @return $foreground;
}

// Unique to Photoshop
//--------------------------------
// Color Blend
//--------------------------------
@function blend-colorblend ($foreground, $background) {
  $foreground-hsv: color-to-hsv($foreground);
  $background-hsv: color-to-hsv($background);
  $bm-hsv: nth($foreground-hsv, 1), nth($foreground-hsv, 2), nth($background-hsv, 3);
  $bm-color: hsv-to-color($bm-hsv);
  @return blend-normal(rgba(red($bm-color), green($bm-color), blue($bm-color), opacity($foreground)), $background);
}

//--------------------------------
// Dissolve
//--------------------------------
@function blend-dissolve ($foreground, $background) {
  // The Dissolve blend mode acts on transparent and partially transparent pixels
  // it treats transparency as a pixel pattern and applies a diffusion dither pattern.
  // @see http://photoblogstop.com/photoshop/photoshop-blend-modes-explained
  @return $foreground;
}

//--------------------------------
// Divide
//--------------------------------
@function blend-divide ($foreground, $background) {
  $bm-red: blend-divide-colors(red($foreground), red($background));
  $bm-green: blend-divide-colors(green($foreground), green($background));
  $bm-blue: blend-divide-colors(blue($foreground), blue($background));
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

@function blend-divide-colors($foreground, $background) {
  @return min((($background / 255) / ($foreground / 255)) * 255, 255);
}

//--------------------------------
// Hue
//--------------------------------
@function blend-hue ($foreground, $background) {
  $foreground-hsv: color-to-hsv($foreground);
  $background-hsv: color-to-hsv($background);
  $bm-hsv: nth($foreground-hsv, 1), nth($background-hsv, 2), nth($background-hsv, 3);
  $bm-color: hsv-to-color($bm-hsv);
  @return blend-normal(rgba(red($bm-color), green($bm-color), blue($bm-color), opacity($foreground)), $background);
}

//--------------------------------
// Luminosity
//--------------------------------
@function blend-luminosity ($foreground, $background) {
  $foreground-hsv: color-to-hsv($foreground);
  $background-hsv: color-to-hsv($background);
  $bm-hsv: nth($background-hsv, 1), nth($background-hsv, 2), nth($foreground-hsv, 3);
  $bm-color: hsv-to-color($bm-hsv);
  @return blend-normal(rgba(red($bm-color), green($bm-color), blue($bm-color), opacity($foreground)), $background);
}

//--------------------------------
// Saturation
//--------------------------------
@function blend-saturation ($foreground, $background) {
  $foreground-hsv: color-to-hsv($foreground);
  $background-hsv: color-to-hsv($background);
  $bm-hsv: nth($background-hsv, 1), nth($foreground-hsv, 2), nth($background-hsv, 3);
  $bm-color: hsv-to-color($bm-hsv);
  @return blend-normal(rgba(red($bm-color), green($bm-color), blue($bm-color), opacity($foreground)), $background);
}

//--------------------------------
// Subtract
//--------------------------------
@function blend-subtract ($foreground, $background) {
  $bm-red: max(red($background) - red($foreground), 0);
  $bm-green: max(green($background) - green($foreground), 0);
  $bm-blue: max(blue($background) - blue($foreground), 0);
  @return blend-normal(rgba($bm-red, $bm-green, $bm-blue, opacity($foreground)), $background);
}

//--------------------------------
// HSL and HSV
//--------------------------------
// @see https://gist.github.com/1069204
@function hsv-to-hsl($h, $s: 0, $v: 0) {
  @if type-of($h) == 'list' {
    $v: nth($h, 3);
    $s: nth($h, 2);
    $h: nth($h, 1);
  }
  @if unit($h) == 'deg' {
    $h: 3.1415 * 2 * ($h / 360deg);
  }
  @if unit($s) == '%' {
    $s: 0 + ($s / 100%);
  }
  @if unit($v) == '%' {
    $v: 0 + ($v / 100%);
  }
  $ss: $s * $v;
  $ll: (2 - $s) * $v;
  @if $ll <= 1 and $ll != 0 {
    $ss: $ss / $ll;
  } @else if ($ll == 2) {
    $ss: 0;
  } @else {
    $ss: $ss / (2 - $ll);
  }
  $ll: $ll / 2;
  @return 360deg * $h / (3.1415 * 2), percentage(max(0, min(1, $ss))), percentage(max(0, min(1, $ll)));
}

@function hsl-to-hsv($h, $ss: 0, $ll: 0) {
  @if type-of($h) == 'list' {
    $ll: nth($h, 3);
    $ss: nth($h, 2);
    $h: nth($h, 1);
  } @else if type-of($h) == 'color' {
    $ll: lightness($h);
    $ss: saturation($h);
    $h: hue($h);
  }
  @if unit($h) == 'deg' {
    $h: 3.1415 * 2 * ($h / 360deg);
  }
  @if unit($ss) == '%' {
    $ss: 0 + ($ss / 100%);
  }
  @if unit($ll) == '%' {
    $ll: 0 + ($ll / 100%);
  }
  $ll: $ll * 2;
  @if $ll <= 1 {
    $ss: $ss * $ll;
  } @else {
    $ss: $ss * (2 - $ll);
  }
  $v: ($ll + $ss) / 2;
  $s: if($ll + $ss == 0, 0, (2 * $ss) / ($ll + $ss));
  @return 360deg * $h / (3.1415 * 2), percentage(max(0, min(1, $s))), percentage(max(0, min(1, $v)));
}

@function color-to-hsv($color) {
  @return hsl-to-hsv($color);
}

@function hsv-to-color($h, $s: 0, $v: 0) {
  $hsl: hsv-to-hsl($h, $s, $v);
  @return hsl(nth($hsl, 1), nth($hsl, 2), nth($hsl, 3));
}


