For listing variations of blocks/elements @modifiers are available to use on certain elements.
For example, if you have modifiers for an element that you need to document, but don't necessarily want to display in the @markup.
/**
*
*
* @atom Button
* @modifiers
* .btn--primary for use in positive flows
* .btn--secondary for use in alternative flows
* @markup
* ...
*/
.btn {
...
&--primary { /* ... */ }
&--secondary { /* ... */ }
}