A single, empty SVG canvas fills the viewport with no data or marks rendered. The example demonstrates a minimal D3 v5 setup where `select` is imported from the d3 library and used to target the `svg` element, while `document.body.clientWidth` and `clientHeight` capture the available screen dimensions. The `styles.css` fixes the body to the viewport edges with hidden overflow, ensuring the blank canvas remains the sole focus. This serves as a starting template for building visualizations on a clean slate.