This example embeds a static SVG tree illustration as a preview image while performing async data loading with D3 v7. It fetches a CSV file of Nepalese Himalayan peaks, normalizes whitespace-separated headers to commas, trims lines, and parses with `d3.csvParse` and `d3.autoType` to calculate dataset dimensions. The page displays the CSV URL and reports file size plus row and column counts in a styled card layout using CSS custom properties and a green accent theme.