|arguments||The variables that are passed to the parametric mixin. Arguments are optional.|
|is-negation||This indicates whether the guard condition is a |
not condition or not. For example
when not (@type = error) means the mixin will be used whenever the value of
@type is not error.
|ref-variable||This is the variable whose value determines which mixin's properties should be applied to the element. This is mandatory.|
|operator||This is the operator that is used for evaluating the condition. It can be |
<=. This is not mandatory. When the operator and value is not given, the compiler assumes the condition to be
<ref-variable> = true.
|value||The value that is used for evaluating the condition. This is optional but becomes mandatory when an operator is provided.|