This example reproduces a Sol LeWitt art piece using raw SVG and JavaScript, with no external libraries. It shows a grid of horizontal and vertical bars that intersect within two circular masks, creating a geometric composition of alternating stripes and gaps. The code generates 100 horizontal rectangles across the full width and 100 vertical rectangles down the full height, each masked to reveal only the areas inside the circles. The masks are constructed with SVG `mask` elements, combining black and white rects and circles to control visibility, and the result is a clean, minimal visualization of layered line patterns.