variants 

The attribute variants defines the list of variants in which this Modifier is valid. When the attribute is absent the Modifier is valid in all variants.

Attribute Information

Used By

Attribute Group attlist.Modifier

Source 

<xs:attribute name="variants" type="xs:IDREFS">
  <xs:annotation>
    <xs:documentation xml:lang="en-US">The attribute variants defines the list of variants in which this Modifier is valid. When the attribute is absent the Modifier is valid in all variants.</xs:documentation>
  </xs:annotation>
</xs:attribute>

Sample