This example reproduces a Sol LeWitt art piece using D3.js version 6.6.1 in an SVG rendering. It displays a grid of thin horizontal and vertical rectangles, masked so they only appear within two overlapping circular regions at the center of the screen. The code uses `d3.select` to append SVG elements, `d3.range` to generate data arrays, and the `.join()` pattern to bind data to `rect` elements. Two SVG masks (`circle-mask` and `circle-mask-2`) define visibility, with the first using a black background and white circle, the second inverted.