This example shows a grid of horizontal and vertical bars overlaid on an SVG canvas, with a circular symbol-shaped mask revealing a cross-hatched pattern at the center. The visualization uses D3 v7 to generate 100 rectangles in each direction, positioning them by index and sizing them to cover the full viewport width and height. Two masks, created with `d3.symbol` and a star symbol type, are applied to the rectangles to alternate black and white fills, producing the contrasting central motif.