Conditional Formatting for Gauge Visual Based on Slicer Selection

Hello community,

I have a gauge visual that is connected to a slicer to show a % statistic of an individual item in a group.  The visual works correctly when an item is selected from the group in the slicer.  The gauge visual is set to maximum.

However, I need the color of the text of the callout value to be white when the value of the group is zero AND when no items in the slicer are selected.  I got the conditional formatting to work when the value is blank, but I cannot find an option for conditional formatting based on no slicer selection. 

Right now, the value shown in the visual is the largest number from the group when no items are selected.  This creates a misleading statistic.

Any help is greatly appreciated!