Expanded rows auto styling - Profitbase/PowerBI-visuals-FinancialReportingMatrix GitHub Wiki
#Premium feature
You can configure rows to apply a style when they are expanded. The style will be automatically applied to rows when they are expanded and removed when they are collapsed.
You configure this behavior in Formatting pane -> Row expansion -> Apply expansion style. Ensure that Apply expansion style is turned on and then specify the style (Font color, background, font style, etc)