energylink/public/sass/components/_panel_piechart.scss

.piechart-panel {
  position: relative;
  display: table;
  width: 100%;
  height: 100%;

  svg {
    width: 100%;
    height: 100%;
  }

  .piechart-tooltip {
    white-space: nowrap;
    font-size: 12px;
    background-color: #141414;
    color: #d8d9da;
    opacity: 0;
  }

  .piechart-tooltip .piechart-tooltip-time {
    text-align: center;
    position: relative;
    top: -3px;
    padding: 0.2rem;
    font-weight: bold;
    color: #d8d9da;
  }

  .piechart-tooltip .piechart-tooltip-value {
    display: table-cell;
    font-weight: bold;
    padding-left: 15px;
    text-align: right;
  }
}