This block renders the text “Hello D3 version 7” in the center of the page at a huge font size, using the D3 `select` API to target the `body` element and assign the string. The page loads D3 v7 from the unpkg CDN and applies a CSS rule for centered, 13em text. The example serves as a minimal starter template for D3 version 7, demonstrating basic DOM selection and text replacement without additional data or interaction.