A grid of vertical and horizontal striped rectangles, generated with D3 v6, covers the screen. The full-width and full-height strips use `select` and `range` to map data to `rect` elements. Two SVG masks reveal overlapping circular regions: a white-filled circle on a black background shows the horizontal lines, while an inverted cutout mask displays the vertical lines, creating a cross-shaped intersection at the center. Rendering is via SVG with D3's `join` method.