This piece reproduces a Sol LeWitt art concept by layering crossed sets of thin rectangles over the full screen. Two D3 v3 masks, rendered with SVG, alternate inverted fills to create overlapping geometric patterns from symbol shapes. The code uses d3.select, d3.range, d3.symbols, and d3.symbol to generate the marks, with each mask applied to a separate group of rect elements. No data source is involved; the composition is purely procedural, driven by fixed dimensions and symbol types.