Generated by SassMeister.com, the Sass playground.

SassMeister-input.scss

// ---
// Sass (v3.2.9)
// ---


@mixin background-position($width) {
  width: $width;
  background-position: ($width - 20px) center;
}

#foo {
  @include background-position(100px);
}
 
#foo.bar {
  @include background-position(50px);
}

SassMeister-output.css

#foo {
  width: 100px;
  background-position: 80px center;
}

#foo.bar {
  width: 50px;
  background-position: 30px center;
}