microstack/snap-overlay/lib/python2.7/site-packages/openstack_dashboard/themes/ubuntu/horizon/components/_pie_charts.scss

.d3_pie_chart_usage {
  .arc {
    stroke: $gray-light;
    fill: $gray-lighter;
  }
}

.d3_pie_chart_distribution {
  .legend-group {
    padding: 1px $padding-small-vertical;
  }
}