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.thing {
  background-color: #40abf4;
  color: #fff;
  @include angler(-15px, 12%, 'after', 'bottom left');
}

//
// Angler Mixin
//
// Creates angled edges via pseudo elements.
//
// Usage:
//
//  .button--type-1 {
//    @include angler( -25px, 10%, ['before'|'after'], ['top'|'right'|'bottom'|'left'] );
//  }
//
//

@mixin angler( $angle, $width_adj, $position: 'after', $transform_origin: 'bottom left' ) {

  // label for debugging
  $mixin_label: "[ `angler` mixin ]";

  // bootstrap the values
  $angle_stripped: strip-units($angle);
  $width_final: ( $width_adj / 2 ) + 100%;

  // let's determine if we need to use left
  // or right positioning
  $h_position: null;
  @if $position == 'after' {
    $h_position: 'left';
  }
  @else if $position == 'before' {
    $h_position: 'right';
  }
  @else {
    @error "#{$mixin_label}: You must use either `before` or `after` for your position value! Your value is #{$h_position}.";
  }

  // ensure that the width is a percentage
  @if unit($width_adj) != "%" {
    @error "#{$mixin_label}: The width value must be a percentage! Your value is #{$width_adj}.";
  }

  // ensure that the angle value is pixel-based
  @if unit($angle) != "px" {
    @error "#{$mixin_label}: The angle value must be pixel-based! Your value is #{$angle}.";
  }

  // base element styles
  position: relative;
  overflow: visible;
  z-index: 0;

  // pseudo element styles
  &:#{$position} {
    position: absolute;
    z-index: -1;
    top: 0;
    bottom: 0;
    #{$h_position}: 0;
    width: #{$width_final};
    display: block;
    content: "";
    background-color: inherit;
    @include transform( skewX( #{$angle_stripped}deg ) );
    @include transform-origin( #{$transform_origin} );
  }
}