<xs:attributeGroup name="Styling.attrib.class">
    <xs:attribute ref="tts:backgroundColor" />
    <xs:attribute ref="tts:color" />
    <xs:attribute ref="tts:direction" />
    <xs:attribute ref="tts:display" />
    <xs:attribute ref="tts:displayAlign" />
    <xs:attribute ref="tts:dynamicFlow" />
    <xs:attribute ref="tts:extent" />
    <xs:attribute ref="tts:fontFamily" />
    <xs:attribute ref="tts:fontSize" />
    <xs:attribute ref="tts:fontStyle" />
    <xs:attribute ref="tts:fontWeight" />
    <xs:attribute ref="tts:lineHeight" />
    <xs:attribute ref="tts:opacity" />
    <xs:attribute ref="tts:origin" />
    <xs:attribute ref="tts:overflow" />
    <xs:attribute ref="tts:padding" />
    <xs:attribute ref="tts:showBackground" />
    <xs:attribute ref="tts:textAlign" />
    <xs:attribute ref="tts:textDecoration" />
    <xs:attribute ref="tts:textOutline" />
    <xs:attribute ref="tts:unicodeBidi" />
    <xs:attribute ref="tts:visibility" />
    <xs:attribute ref="tts:wrapOption" />
    <xs:attribute ref="tts:writingMode" />
    <xs:attribute ref="tts:zIndex" />
</xs:attributeGroup>