foundation-sites/scss/prototype/_text-transformation.scss

// Foundation for Sites by ZURB
// foundation.zurb.com
// Licensed under MIT Open Source

////
/// @group prototype-text-transformation
////

/// Responsive breakpoints for text transformation classes
/// @type Boolean
$prototype-transformation-breakpoints: $global-prototype-breakpoints !default;

/// Map containing all the `text-transformation` classes
/// @type Map
$prototype-text-transformation: (
  lowercase,
  uppercase,
  capitalize
) !default;

/// Text Transformation, by default coming through a map `$prototype-text-transformation`
/// @param {String} $transformation [] Text Transformation
@mixin text-transform($transformation) {
  text-transform: $transformation !important;
}

@mixin foundation-prototype-text-transformation {
  @each $transformation in $prototype-text-transformation {
    .text-#{$transformation} {
      @include text-transform($transformation);
    }
  }

  @if ($prototype-transformation-breakpoints) {
    // Loop through Responsive Breakpoints
  	@each $size in $breakpoint-classes {
      @include breakpoint($size) {
        @each $transformation in $prototype-text-transformation {
          @if $size != $-zf-zero-breakpoint {
            .#{$size}-text-#{$transformation} {
  			      @include text-transform($transformation);
  			    }
          }
        }
      }
    }
  }
}