title: Change node color in D3 sankey diagram
body: <p>How could I change the node color in <a href="https://observablehq.com/@brunurb/flow-o-matic-sankey-silvia" rel="nofollow noreferrer">this sankey diagram</a></p>
  <p>I wanted the two bottom central nodes to be the same color as the previous link color (in this case the bottom node red and the one above it orange)
  Noob here, thanks in advance for your help.</p>