SASS: How do I use these grid maps?

I was introduced to the gridlover tool . It provides SASS variables, for example:

$scale0: (
  fontSize: 1em,
  line: 1.5em,
  autoLineCount: 1,
  autoLineHeight: 1.5em
);

      

        
        
        
      

    

But I cannot figure out which matches all values.

I understand that I can use each one using map-get

. fontSize

is obviously used for installation font-size

and line

looks like line-height

.

.some-class {
  font-size: map-get($scale0, fontSize);
  line-height: map-get($scale0, line);
}

      

        
        
        
      

    

But what is autoLineCount

and autoLineHeight

? Are these keywords SASS? What should I do with them?