svg text {
    -webkit-user-select: none;
       -moz-user-select: none;
        -ms-user-select: none;
            user-select: none;
}
svg text::selection {
    background: none;
}

.tree-links line {
  stroke: #999;
  stroke-opacity: 0.2;
  cursor:pointer;
  stroke-width:8px;
}

.tree-nodes circle {
  stroke: #000;
  stroke-width:1.5px;  
  cursor:pointer;
}

.tree-labels text {
  fill: #000;
  font-size:0.8em;
  cursor:pointer;
}