This example uses D3.js (v5) to visualize a network of chemical compounds, targets, and annotations as linked circles. It shows how nodes are arranged in three concentric rings based on their group—compounds on the outer ring, targets on the middle, and annotations at the center—using `d3.forceSimulation` with a custom `forceRadial` constraint. Links between nodes are rendered as black lines, with stroke width and class names indicating link type. The code loads `nodes.csv` and `links.csv`, then applies forces for collision, link distance, and radial positioning. The resulting static SVG chart is built entirely through D3’s data-join and tick event updates.