.node_link .node > circle {
  
  fill: #EDD;
  stroke: #A99;
  stroke-width: 2px;
}

.node_link .node > text {
  font-family: sans-serif;
  text-anchor: middle;
  pointer-events: none;
  font-weight: bold;
  font-size: 12px;
  text-shadow: -1px -1px white, -1px 1px white, 1px 1px white, 1px -1px white, -1px 0 white, 0 1px white, 1px 0 white, 0 -1px white;
  
  -webkit-touch-callout: none; /* iOS Safari */
  -webkit-user-select: none;   /* Chrome/Safari/Opera */
  -khtml-user-select: none;    /* Konqueror */
  -moz-user-select: none;      /* Firefox */
  -ms-user-select: none;       /* IE/Edge */
  user-select: none;           /* non-prefixed version, currently
                                  not supported by any browser */
}

.node_link .link {
  stroke: #CCD;
  stroke-width: 4px;
  opacity: 0.6;
}
.node_link .directed.link {
  marker-end: url(#end-arrow);
}
.node_link #end-arrow {
  fill: #CCD;
}