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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              <h1 class="title">
  The responsive-font-size mixin
</h1>

<article class="article">
  <h2 class="article__title">
    Automated font-size rescaling with SCSS
  </h2>
  <p class="article__date">
    2017/12/21
  </p>
  <p class="article__content">
    This text automatically rescales thanks to the <a href="https://github.com/MartijnCuppens/postcss-rfs">RFS mixin</a>. It uses the RFS algorithm to automatically calculate the appropriate font size based on the dimensions of the monitor or device.
  </p>
</article>
<article class="article">
  <h2 class="article__title">PostCSS alternative</h2>
  <p class="article__content">
      A <a href="https://github.com/MartijnCuppens/postcss-rfs" target="_blank">PostCSS plugin</a> is available which uses the <code>responsive-font-size</code> property.<br>
    <i>
    <b>Update:</b> In the meanwhile the PostCSS plugin is also included in the main RFS project.
    </i>
    </p>
</article>
<article class="article">
  <h2 class="article__title">RFS in Bootstrap?</h2>
  <p class="article__content">Currenty there is an open feature-request to put RFS in Bootstrap: <a href="https://github.com/twbs/bootstrap/issues/23053">Responsive font sizes</a>. The result of RFS in Bootstrap is shown on <a href="http://martijncuppens.github.io/rfs/">the bootstrap RFS demo site</a>.<br>
    <i>
    <b>Update:</b> In the meanwhile RFS is also included in Bootstrap.
  </i>
    </p>
</article>
<article class="article disable-rfs">
  <h2 class="article__title">Disable responsive font-size</h2>
  <div class="article__content">Responsive font-sizing can be disabled within an element by adding the <code>.disable-rfs</code> class
  <br>
    <i>
    <b>Update:</b> In the meanwhile this feature is disabled by default because it generates more css. You can enable it by setting <code>$rfs-class: "disable"</code> in scss like in this codepen.
  </i>
  </div>
</article>
<article class="article">
  <h2 class="article__title">Lorem ipsum text</h2>
  <div class="article__content">No demo without Lorem ipsum text. Lorem ipsum dolor sit amet, consectetur adipisicing elit. Provident tenetur delectus fuga et, doloribus rerum! Aperiam voluptate mollitia rerum necessitatibus repudiandae asperiores doloremque deleniti praesentium,
    dolorem maxime, quia, libero. Maiores? Lorem ipsum dolor sit amet, consectetur adipisicing elit. Iste distinctio quidem, obcaecati aperiam! Distinctio porro pariatur labore veniam deserunt mollitia consectetur unde voluptatem blanditiis eaque aperiam,
    sequi sed vero debitis!</div>
</article>
            
          
!
            
              // $enable-rfs: false;

// stylelint-disable property-blacklist, scss/dollar-variable-default

// SCSS RFS mixin
//
// Automated responsive values for for font sizes, paddings, margins and much more
//
// Licensed under MIT (https://github.com/twbs/rfs/blob/master/LICENSE)

// Configuration

// Base value
$rfs-base-value: 1.25rem !default;
$rfs-unit: rem !default;

@if $rfs-unit != rem and $rfs-unit != px {
  @error "`#{$rfs-unit}` is not a valid unit for $rfs-unit. Use `px` or `rem`.";
}

// Breakpoint at where values start decreasing if screen width is smaller
$rfs-breakpoint: 1200px !default;
$rfs-breakpoint-unit: px !default;

@if $rfs-breakpoint-unit != px and $rfs-breakpoint-unit != em and $rfs-breakpoint-unit != rem {
  @error "`#{$rfs-breakpoint-unit}` is not a valid unit for $rfs-breakpoint-unit. Use `px`, `em` or `rem`.";
}

// Resize values based on screen height and width
$rfs-two-dimensional: false !default;

// Factor of decrease
$rfs-factor: 10 !default;

@if type-of($rfs-factor) != number or $rfs-factor <= 1 {
  @error "`#{$rfs-factor}` is not a valid  $rfs-factor, it must be greater than 1.";
}

// Mode. Possibilities: "min-media-query", "max-media-query"
$rfs-mode: min-media-query !default;

// Generate enable or disable classes. Possibilities: false, "enable" or "disable"
$rfs-class: disable !default; // This demo only

// 1 rem = $rfs-rem-value px
$rfs-rem-value: 16 !default;

// Safari iframe resize bug: https://github.com/twbs/rfs/issues/14
$rfs-safari-iframe-resize-bug-fix: true !default; // This demo only

// Disable RFS by setting $enable-rfs to false
$enable-rfs: true !default;

// Cache $rfs-base-value unit
$rfs-base-value-unit: unit($rfs-base-value);

// Remove px-unit from $rfs-base-value for calculations
@if $rfs-base-value-unit == px {
  $rfs-base-value: $rfs-base-value / ($rfs-base-value * 0 + 1);
}
@else if $rfs-base-value-unit == rem {
  $rfs-base-value: $rfs-base-value / ($rfs-base-value * 0 + 1 / $rfs-rem-value);
}

// Cache $rfs-breakpoint unit to prevent multiple calls
$rfs-breakpoint-unit-cache: unit($rfs-breakpoint);

// Remove unit from $rfs-breakpoint for calculations
@if $rfs-breakpoint-unit-cache == px {
  $rfs-breakpoint: $rfs-breakpoint / ($rfs-breakpoint * 0 + 1);
}
@else if $rfs-breakpoint-unit-cache == rem or $rfs-breakpoint-unit-cache == "em" {
  $rfs-breakpoint: $rfs-breakpoint / ($rfs-breakpoint * 0 + 1 / $rfs-rem-value);
}

// Calculate the media query value
$rfs-mq-value: if($rfs-breakpoint-unit == px, #{$rfs-breakpoint}px, #{$rfs-breakpoint / $rfs-rem-value}#{$rfs-breakpoint-unit});
$rfs-mq-property-width: if($rfs-mode == max-media-query, max-width, min-width);
$rfs-mq-property-height: if($rfs-mode == max-media-query, max-height, min-height);

// Internal mixin used to determine which media query needs to be used
@mixin _rfs-media-query {
  @if $rfs-two-dimensional {
    @media (#{$rfs-mq-property-width}: #{$rfs-mq-value}), (#{$rfs-mq-property-height}: #{$rfs-mq-value}) {
      @content;
    }
  }
  @else {
    @media (#{$rfs-mq-property-width}: #{$rfs-mq-value}) {
      @content;
    }
  }
}

// Internal mixin that adds disable classes to the selector if needed.
@mixin _rfs-rule {
  @if $rfs-class == disable and $rfs-mode == max-media-query {
    // Adding an extra class increases specificity, which prevents the media query to override the property
    &,
    .disable-rfs &,
    &.disable-rfs {
      @content;
    }
  }
  @else if $rfs-class == enable and $rfs-mode == min-media-query {
    .enable-rfs &,
    &.enable-rfs {
      @content;
    }
  }
  @else {
    @content;
  }
}

// Internal mixin that adds enable classes to the selector if needed.
@mixin _rfs-media-query-rule {

  @if $rfs-class == enable {
    @if $rfs-mode == min-media-query {
      @content;
    }

    @include _rfs-media-query {
      .enable-rfs &,
      &.enable-rfs {
        @content;
      }
    }
  }
  @else {
    @if $rfs-class == disable and $rfs-mode == min-media-query {
      .disable-rfs &,
      &.disable-rfs {
        @content;
      }
    }
    @include _rfs-media-query {
      @content;
    }
  }
}

// Helper function to get the formatted non-responsive value
@function rfs-value($values) {
  // Convert to list
  $values: if(type-of($values) != list, ($values,), $values);

  $val: '';

  // Loop over each value and calculate value
  @each $value in $values {
    @if $value == 0 {
      $val: $val + ' 0';
    }
    @else {
      // Cache $fs unit
      $unit: if(type-of($value) == "number", unit($value), false);

      @if $unit == "" {
        // Add appropriate unit
        $val: $val + ' ' + if($rfs-unit == rem, #{$value / $rfs-rem-value}rem, #{$value}px);
      }
      @else if $unit == px {
        // Convert to rem if needed
        $val: $val + ' ' + if($rfs-unit == rem, #{$value / ($value * 0 + $rfs-rem-value)}rem, $value);
      }
      @else if $unit == rem {
        // Convert to px if needed
        $val: $val + ' ' + if($rfs-unit == px, #{$value / ($value * 0 + 1) * $rfs-rem-value}px, $value);
      }
      @else {
        // If $fs isn't a number (like inherit) or $fs has a unit (not px or rem, like 1.5em) or $ is 0, just print the value
        $val: $val + ' ' + $value;
      }
    }
  }

  // Remove first space
  @return str-slice($val, 2);
}

// Helper function to get the responsive value calculated by RFS
@function rfs-fluid-value($values) {
  // Convert to list
  $values: if(type-of($values) != list, ($values,), $values);

  $val: '';

  // Loop over each value and calculate value
  @each $value in $values {
    @if $value == 0 {
      $val: $val + ' 0';
    }

    @else {
      // Cache $fs unit
      $unit: if(type-of($value) == "number", unit($value), false);

      // If $fs isn't a number (like inherit) or $fs has a unit (not px or rem, like 1.5em) or $ is 0, just print the value
      @if not $unit or $unit != "" and $unit != px and $unit != rem {
        $val: $val + ' ' + $value;
      }

      @else {
        // Remove unit from $fs for calculations
        @if $unit == px {
          $value: $value / ($value * 0 + 1);
        }
        @else if $unit == rem {
          $value: $value / ($value * 0 + 1 / $rfs-rem-value);
        }

        // Only add the media query if the value is greater than the minimum value
        @if $value <= $rfs-base-value or not $enable-rfs {
          $val: $val + ' ' +  if($rfs-unit == rem, #{$value / $rfs-rem-value}rem, #{$value}px);
        }
        @else {
          // Calculate the minimum value
          $value-min: $rfs-base-value + ($value - $rfs-base-value) / $rfs-factor;

          // Calculate difference between $value and the minimum value
          $value-diff: $value - $value-min;

          // Base value formatting
          $min-width: if($rfs-unit == rem, #{$value-min / $rfs-rem-value}rem, #{$value-min}px);

          // Use `vmin` if two-dimensional is enabled
          $variable-unit: if($rfs-two-dimensional, vmin, vw);

          // Calculate the variable width between 0 and $rfs-breakpoint
          $variable-width: #{$value-diff * 100 / $rfs-breakpoint}#{$variable-unit};

          // Return the calculated value
          $val: $val + ' ' + calc(#{$min-width} + #{$variable-width});
        }
      }
    }
  }

  // Remove first space
  @return str-slice($val, 2);
}

// RFS mixin
@mixin rfs($values, $property: font-size) {
  $val: rfs-value($values);
  $fluidVal: rfs-fluid-value($values);

  // Do not print the media query if responsive & non-responsive values are the same
  @if $val == $fluidVal {
    #{$property}: #{$val};
  }
  @else {
    @include _rfs-rule {
      #{$property}: unquote(if($rfs-mode == max-media-query, $val, $fluidVal));

      // Include safari iframe resize fix if needed
      min-width: if($rfs-safari-iframe-resize-bug-fix, (0 * 1vw), null);
    }

    @include _rfs-media-query-rule {
      #{$property}: unquote(if($rfs-mode == max-media-query, $fluidVal, $val));
    }
  }
}

// Shorthand helper mixins
@mixin font-size($value) {
  @include rfs($value);
}

@mixin padding($value) {
  @include rfs($value, padding);
}

@mixin padding-top($value) {
  @include rfs($value, padding-top);
}

@mixin padding-right($value) {
  @include rfs($value, padding-right);
}

@mixin padding-bottom($value) {
  @include rfs($value, padding-bottom);
}

@mixin padding-left($value) {
  @include rfs($value, padding-left);
}

@mixin margin($value) {
  @include rfs($value, margin);
}

@mixin margin-top($value) {
  @include rfs($value, margin-top);
}

@mixin margin-right($value) {
  @include rfs($value, margin-right);
}

@mixin margin-bottom($value) {
  @include rfs($value, margin-bottom);
}

@mixin margin-left($value) {
  @include rfs($value, margin-left);
}






/////////////
// Theming //
/////////////
html {
  background: #e2ebef;
}

body {
  max-width: 1200px;
  padding: 20px;
  margin: 0 auto;
  line-height: 1.2;
  font-weight: 300;
  font-family: Roboto Slab, sans-serif;
}

.title{
  @include font-size(4rem);
  margin: 0 0 .5em;
  font-weight: 600;
}

.article{
  background: white;
  box-shadow: 0 0 15px rgba(black, .15);
  padding: 20px 25px;
  border-radius: .5rem;
  
  &:not(:first-of-type){
    margin-top: 2rem;
  }
  
  &__title{
    @include font-size(27px);
    margin: 0;
    font-weight: 600;
  }
  
  &__date{
    padding-top: .25em;
    @include font-size(12);
    opacity: .75;
    font-style: italic;
    margin: 0;
  }
  
  &__content{
    padding-top: .75em;
    @include font-size(16);
    margin: 0;
    line-height: 1.4;
  }
}
            
          
!
999px
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