This visualization compares the popularity trends of Python, JavaScript, and Java across 20 days using two side-by-side SVG charts. The top line chart maps each language's daily score with `d3.line` paths, while the bottom combined chart overlays Python bars (`d3.scaleBand`) with a JavaScript line (`d3.line`). Both include grid lines, axes, and legends built with D3 v7 APIs (`d3.select`, `d3.scaleLinear`, `d3.axisBottom`, `d3.axisLeft`). The synthetic dataset is embedded directly in the JavaScript code.