This example renders a simple line chart with twenty-one randomly generated data points using D3 version 5. The chart uses `d3.scaleLinear` for both axes and `d3.line` with `d3.curveMonotoneX` smoothing to draw the line, while individual data points appear as circles. The SVG output is styled with CSS classes for the line and dots, and mouseover events log data to the console. The visualization demonstrates basic D3 plotting techniques without external data sources, relying on `d3.randomUniform` for its synthetic dataset.