Generated by SassMeister.com.

SassMeister-input.scss

// ----
// Sass (v3.4.14)
// Compass (v1.0.3)
// Modular Scale (v2.1.1)
// ----

@import 'modular-scale';
@mixin ml($range...) {
  @if $ms-range == null {$ms-range: $range !global;}
  @include ms-respond(line-height, 1, $range, 1);
}

foo {
  @include ml(
    1.1  20em,
    1.4  40em
  );
}

SassMeister-output.css

foo {
  line-height: 1.1;
}
@media (min-width: 20em) and (max-width: 40em) {
  foo {
    line-height: calc( 1.1 + 0.3 * ( ( 100vw - 20em) / 20 ) );
  }
}
@media (min-width: 40em) {
  foo {
    line-height: 1.4;
  }
}