This visualization displays COVID-19 case counts for the top 20 countries using horizontal bars rendered as SVG rectangles. The chart maps country names along the y-axis with a D3 scaleBand and case numbers along the x-axis with a scaleLinear. React manages the component state and lifecycle, fetching CSV data from a GitHub gist via d3.csv. Axes are manually constructed by mapping over tick values to generate line and text elements. The bars are colored green through CSS, with red gridlines marking x-axis tick positions.