This example generates a geometric pattern of black bars overlaid on a white background using D3 version 7. It displays 100 horizontal and 100 vertical rectangles, each masked to reveal shapes: the horizontal bars are clipped by a wye symbol, while the vertical bars are masked by a star with a rectangular cutout. The code uses `d3.select`, `d3.range`, `d3.symbol`, and SVG `<mask>` elements to compose the layered effect, rendering fully in SVG with no external data source.