This snippet computing golden ratio field for SASS/SCSS

scale.scss

@function scaleMath($n) {
	@if $n == 0 {@return 1;}
	@if $n == 1 {@return 1.618;}
	@if $n == -1 {@return 0.618;}

	@if $n > 0{
		@return scaleMath($n - 1) + scaleMath($n - 2);
	}
	@if $n < 0 {
		@return scaleMath($n + 2) - scaleMath($n + 1);
	}
}


// example
.container {
  width: #{scaleMath(-3)}; // 0.236
}
// or
@function scaleRem($val){
  @return #{scaleMath($val)}rem;
}
.container {
  width: scaleRem(2); // 2.618rem
}