This example demonstrates SVG fundamentals by layering horizontal and vertical striped rectangles that intersect to create a grid, with two masks applied to each set of stripes. D3’s `select`, `range`, `symbol`, and `symbols` APIs generate the stripes and position symbol paths within the masks. The `mask1` and `mask2` masks, filled with black and white respectively, reveal or hide portions of the grid based on the symbol shapes, producing a dynamic interplay of light and dark geometric patterns across the full canvas.