Custom Theme not working

Hi,

I have multiple visuals in my report and instead of controlling the colors manually , I want to create custom theme to control the colors at one place so that I don't have to do it again and again for similar visuals.

I wrote following JSON file which I can import successfully but the color never changes as expected.

I need the customization for pieChart, PivotTable, hundredPercentStackedBarChart etc.

Sample code

{
     "name": "MyTheme",
     "dataColors": ["#94B6D2","#88909A","#88919A","#677E94","#94B5D4","#B3B3B3"],
     "background":"#CCCCCC",
     "foreground": "#666666",
     "tableAccent": "#568410",
     "visualStyles":{
             "pieChart": {
                     "*": {
                                            "dataColors": ["#99CC66","#FF0099","#6600CC","#660000"]
                                           }  
                               }
                            }
}

I was playing around with names and properties but nothing working. Can someone help please