This D3.js (v7) reproduction of Sol LeWitt’s Wall Drawing #370 uses SVG masks to create a circular viewing window. The code generates 100 horizontal and 100 vertical striped rectangles across the full canvas, with each set masked to reveal either a white circle on black or a black circle on white. The two masks are defined as `mask` and `mask2`, each containing a full-canvas rect and a 200-pixel-radius circle positioned at the center. The `select` and `range` APIs are used to construct the repeating rect elements via joins.