This example shows a grid of alternating horizontal and vertical white rectangles on a black background, with two circular cutouts that create a cross-like overlapping pattern. It uses the Document Object Model (DOM) API to create SVG elements programmatically, including `document.createElementNS` for `svg`, `rect`, and `circle` nodes. Two SVG masks, `circle-mask` and `circle-mask2`, use contrasting fill colors to reveal or hide the rectangles. The code generates 100 horizontal rectangles and 100 vertical rectangles with fixed spacing, applying the masks to produce the final geometric composition.