This example demonstrates how a D3.js visualization can automatically adapt to its container size. A green X-shaped set of lines is drawn inside an SVG, and the entire graphic redraws whenever the browser window is resized. The code uses a fixed-position `#chart` div that fills the page, with `clientWidth` and `clientHeight` extracting the computed dimensions. Those values then set the SVG’s `width` and `height` attributes, and the lines are repositioned via a `redraw` function wired to the window’s `resize` event. The rendering uses SVG elements and D3’s data join pattern.