This visualization displays heterogeneity bands from a metadata JSON file, with each study represented as a horizontal line and its confidence interval as a filled rectangular band. The bands use CSS `mix-blend-mode: multiply` to create darker overlaps where intervals intersect, revealing shared regions across studies. Implemented with D3 v6, the code uses `scaleLinear` for the x-axis, `scalePoint` for study positioning, and appends SVG `<rect>` and `<line>` elements to show the data from a gist-hosted dataset.