This example animates a time-series area and line chart of temperature data from San Francisco, loading the dataset from a remote CSV file. The visualization reveals temperature trends over time, with a gradient-filled area beneath a red line that smoothly updates as new data points are appended. Built with D3 v5, it uses `csv()` to parse the data, `scaleTime` and `scaleLinear` for axes, and the `area` and `line` generators with a basis curve. A transition loop sequentially shifts data through the chart, redrawing both paths to create a flowing effect.