line {
  stroke-width: 2;
  stroke: gray;
}

circle {
  stroke: white;
}

.svg-center {
  display: flex;
  justify-content: center;
  align-items: center;
}

.focus {
  opacity: 1;
}

.out-of-focus {
  opacity: 0.2;
}

.source {
  opacity: 1;
  stroke: black;
  stroke-width: 2px;
}

/* g text {
  color: black;
  -webkit-text-fill-color: white; 
  -webkit-text-stroke-width: 1px;
  -webkit-text-stroke-color: black;
} */

/* g text {
    visibility: hidden;
}

g:hover text {
    visibility: visible;
} */