This example reproduces a Sol LeWitt art piece using D3, rendering 100 horizontal and 100 vertical rectangles that intersect in a grid-like pattern. The visualization shows a central circular area where the rectangles are visible, while the surrounding regions are masked out. It uses d3.select to create an SVG, d3.range with data joins to generate the rectangles, and SVG mask elements with circles to create the circular cutout effect. The code iterates through both orientations to layer the marks.