This example reproduces a Sol LeWitt-inspired generative drawing using raw SVG and D3 selection utilities. It shows a grid of thick horizontal and vertical bars intersecting across the full viewport, with a circular mask revealing a clean white center where the lines are hidden. Two SVG masks stack to selectively hide and show line segments: the first mask clips horizontal bars through a black rectangle with a white circular hole, while the second inverts this to mask vertical bars. The code constructs all elements dynamically via `document.createElementNS` and appends them to the page, relying on D3's `selection` import for utility but primarily using native DOM APIs.