Fork of Path Animation
This visualization displays personal body weight data over time for a single individual, with the y-axis representing weight in kilograms and the x-axis representing dates. Two smoothed line paths are rendered from the dataset, each colored differently to distinguish between weight series. A slider control animates two circles moving along these paths, using `path.getPointAtLength` to track progress from the beginning to the end of each line. The chart is built with D3 v5, using `scaleTime`, `scaleLinear`, `scaleOrdinal`, and `curveBasis` to generate the SVG paths and axes.