add-selector($selector = '', $value = '', $extends...) {
  {get-selectors($selector, $value)} {
    {block}
  }
}

add-value($value, $extends...) {
  $first = true
  $selector = '';

  for $v in $value {
    if !$first {
      $selector = $selector + ', &';
    }
    $selector = $selector + selector-name(_.current_selector, $v);
    $first = false
  }

  &{$selector} {
    add-extends($extends)
    {block}
  }
}

add-extends($extends) {
  for $extend in $extends {
    @extends $--{$breakpoint}-{$extend}
  }
}

get-visible-color($color-value, $property = 'font') {
  $color = 'light'
  if light($color-value) {
    $color = 'dark'
  }
  add-extends('color-' + $property + '-' + $color)
}

shadow-values($i = 1) {
  box-shadow: shadow-calc($Shadows.first.x_min, $Shadows.first.x_max, $i) shadow-calc($Shadows.first.y_min, $Shadows.first.y_max, $i) shadow-calc($Shadows.first.blur_min, $Shadows.first.blur_max, $i) shadow-calc($Shadows.first.spread_min, $Shadows.first.spread_max, $i) alpha($Shadows.first.color, $Shadows.first.opacity),
          shadow-calc($Shadows.second.x_min, $Shadows.second.x_max, $i) shadow-calc($Shadows.second.y_min, $Shadows.second.y_max, $i) shadow-calc($Shadows.second.blur_min, $Shadows.second.blur_max, $i) shadow-calc($Shadows.second.spread_min, $Shadows.second.spread_max, $i) alpha($Shadows.second.color, $Shadows.second.opacity),
          shadow-calc($Shadows.third.x_min, $Shadows.third.x_max, $i) shadow-calc($Shadows.third.y_min, $Shadows.third.y_max, $i) shadow-calc($Shadows.third.blur_min, $Shadows.third.blur_max, $i) shadow-calc($Shadows.third.spread_min, $Shadows.third.spread_max, $i) alpha($Shadows.third.color, $Shadows.third.opacity)
}

webfont(family, file, hack-chrome-windows = false, weight = 'normal')
  @font-face
    font-family family
    src url(font-url(file + '.eot'))
    src url(font-url(file + '.eot?#iefix')) format('embedded-opentype'),
    url(font-url(file + '.woff')) format('woff'),
    url(font-url(file + '.woff2')) format('woff2'),
    url(font-url(file + '.ttf')) format('truetype')
    font-weight weight
    font-style normal
  if hack-chrome-windows
    @media screen and (-webkit-min-device-pixel-ratio: 0)
      @font-face
        font-family family
        src url(font-url(file + '.svg#' + family)) format('svg')