This visualization displays daily surface temperatures since 1940, with one line per year rendered as an SVG path. The code uses Svelte’s reactivity and D3’s `csv`, `scaleLinear`, `extent`, `line`, `groups`, and `curveCatmullRom` to map day-of-year and temperature values. Recent years (2023–2024) are highlighted with distinct colors and increased opacity, while older years fade into the background. Data comes from Climate Reanalyzer’s world daily temperature record, with a dark gradient backdrop and legend overlay.