This example reproduces a Sol LeWitt-inspired geometric composition using D3. It shows a grid of horizontal and vertical striped rectangles intersecting over a central circular opening, created through two SVG mask layers. The code uses D3 selections, `data` binding with `range(n)`, and the `join('rect')` pattern to generate the marks. Each mask combines a full-size rect with a circle to reveal or hide portions of the grid. The rendering is done in SVG, sized to the full browser window.