This example reproduces a Sol LeWitt-style geometric drawing using only SVG elements and masks. It displays a grid of 100 horizontal and vertical stripes that are visible only within two circular regions at the center of the canvas. The code creates the pattern by appending rectangle elements with alternating orientations, applying SVG `mask` and `mask2` elements with circle and inverted circle cutouts to control visibility. It relies on raw DOM manipulation via `createElementNS` and `setAttribute` rather than D3, with no external data source or animation.