Generated by SassMeister.com.

SassMeister-input.scss

// ----
// libsass (v3.2.5)
// ----

$font-size-huge: 4.8rem;
$font-size-bigger: 3.4rem;
$font-size-big: 2.8rem;
$font-size-heading: 2.4rem;
$font-size-hero: 2.1rem;
$font-size-large: 1.8rem;
$font-size-normal: 1.6rem;
$font-size-medium: 1.4rem;
$font-size-default: 1.2rem;
$font-size-small: 1.1rem;
$font-size-tiny: 1rem;
$font-size-micro: 0.9rem;
$font-size-nano: 0.8rem;

$line-height-map: (
  1   : 1.5,
  1.2 : 1.5,
  1.4 : 1.5,
  1.6 : 1.375,
  1.8 : 1.33333333,
  2.1 : 1.33333333,
  2.4 : 1.25,
  2.8 : 1.25,
  3.2 : 1.25,
  4.8 : 1.125
);

@function strip-units($number) {
  @return $number / ($number * 0 + 1);
}

@mixin font-size($size, $height: true, $important: false) {
  $bang: '';
  $line-height: '';

  @if $important {
    $bang: ' !important';
  }
  
  @if $height == true {
    $line-height: map-get($line-height-map, strip-units($size));
  } @else if $height == false {
    $line-height: 1;
  } @else {
    $line-height: $height;
  }
  
  font-size: $size unquote($bang);
  line-height: $line-height;
}

div {
  @include font-size($font-size-large);
}

SassMeister-output.css

div {
  font-size: 1.8rem ;
  line-height: 1.33333;
}