This example generates a full-screen grid of 100 vertical and horizontal bars using D3 selections and joins, then applies two circular SVG masks to create a striking cross-hatch pattern. Built with a React-wrapped D3 v6 setup, the code uses `select`, `range`, and `join` to bind data to rectangles, while the masks—one with a white circle on black, the other inverted—reveal and hide intersecting lines around a central focal point.