svg {
  display: block;
  fill: none;
  margin: auto;
  stroke: currentColor;
  stroke-width: 2px;
  stroke-linejoin: bevel;
}
marker, text {
  fill: currentColor;
  stroke: none;
}
text {
  font-family: Fira Math, Arial, sans-serif;
  font-size: 11pt;
}
.var {
  font-style: italic;  
}
.arrow {
  marker-end: url(#arrow);
  stroke-width: 1px;
}
.element {
  marker-mid: url(#node);
  marker-end: url(#node);
}
.subscript {
  font-size: 70%;
  baseline-shift: sub;
}