.chart text {
  fill: black;
}
.chart line {
  stroke: black;
}
.chart path {
  stroke: black;
}
.c3 path,
.c3 line {
  stroke: black;
}

.c3-tooltip,
.c3-tooltip td {
  background: rgba(0,0,0,0.8);
  color: #fff;
}
.c3-tooltip th {
  font-family: 'Roboto', sans-serif;
  background: rgba(255,255,255,0.0);
  /*background: black;*/
}