Open Chord Shared Ad Blocks
This interactive chord diagram visualizes the shared advertising blocks among five soda brands: 7-Up, A&W, Coke, Dr Pepper, and Pepsi. Each ribbon’s thickness and color encode the number of shared ad placements between brand pairs, with tooltips revealing exact counts. Built with D3 v3, the layout uses `d3.layout.chord()` for the matrix-based chord geometry, while SVG paths and arcs render the groups and ribbons with mouseover fading. The diagram supports responsive resizing via a `viewBox` and `preserveAspectRatio` attributes.