This visualization presents a side-by-side bar chart comparing student grades across different sleep patterns, with the bars for each sleep category grouped by grade level. The chart is built using D3.js v7, which loads a CSV file from a GitHub gist, groups the data with the `d3.rollups` API, and scales using `d3.scaleBand` and `d3.scaleLinear`. Hovering over a bar triggers a tooltip that displays the sleep pattern, grade, and count, with the visualization rendered as SVG elements.