This example reproduces a Sol LeWitt art piece using D3.js, showing intersecting horizontal and vertical line patterns constrained by two circular masks. It demonstrates how SVG mask elements can create layered visual effects with geometric precision. The code uses D3 selections with `join('rect')` to bind 100 data points from `range(n)`, while two distinct mask groups apply inverted black-and-white circles to reveal the gridlines. The visualization renders as an SVG using dynamic width and height based on the window size.