#holc_ads {
   polygon-opacity: 0.7;
   line-color: #444;
   line-width: 0;
   line-opacity: 1;
  polygon-comp-op: overlay;
}

#holc_ads[grade='a'] {
   polygon-fill: #418e41;
}
#holc_ads[grade='c'] {
   polygon-fill: #ffdf00;
}
#holc_ads[grade='b'] {
   polygon-fill: #4a4ae4;
}
#holc_ads[grade='d'] {
   polygon-fill: #eb3f3f;
}
#holc_ads[grade=null] {
   polygon-fill: #ccc;
  line-width: 0.5
}

