This example demonstrates a minimal D3 starter project that renders a single rotated red SVG rectangle, with an interactive tooltip that appears on mouseover. The page uses D3 v7, imported via a bundled script, to select the body element and append both the SVG and a tooltip div. JavaScript event handlers on the rectangle trigger D3 selections and transitions to control the tooltip’s opacity and text content, while the tooltip’s position is set using the event’s page coordinates. The visualization is purely static apart from this interaction, showcasing basic SVG drawing and event handling in D3.