The differential style a rule applies — the OOXML dxf, as the facets it actually names.
Parameters
style: Properties<Serializable>|null|undefined
Returns string|null
Remarks
Not a diff against Normal like a style region's payload: a dxf is already a diff, so every
property present in it is by construction something the rule author set. Absent facets are not
reported — a rule that only fills says fill #FFFF00 and nothing about the font it leaves alone.
The differential style a rule applies — the OOXML
dxf, as the facets it actually names.