Alloy.CFG not working on android tss

I have defined a theme color in config.json and used it in tss as follows:

config.json
{
  "global": {
    "ThemeColor":"#00A74C"
  },
  "env:development": {},
  "env:test": {},
  "env:production": {},
  "os:android": {},
  "os:blackberry": {},
  "os:ios": {},
  "os:mobileweb": {},
  "dependencies": {
  }
}
 
app.tss
".headerLbl":{
    color:Alloy.CFG.ThemeColor
}
 
view
<Label id="headername" text="sample" class="headerLbl"></Label>