This example demonstrates a WebCola layout with grouped nodes, where rectangular clusters highlight relationships between connected elements in a network. The visualization uses the WebCola adaptor with `d3.v4` to compute the force-directed layout, applying `avoidOverlaps(true)` and custom group bounds to keep nodes and their enclosing rectangles distinct. Node and group drag interactions are enabled via `cola.drag`, while a `d3.zoom` handler transforms the SVG root for pan and zoom. The data comes from a JSON file containing node metadata, links, and hierarchical group definitions, rendered as SVG rectangles, lines, and text labels.