This example renders a fixed composition of overlapping circles and rectangles on a full-screen SVG canvas. The visualization displays fourteen geometric shapes, each defined with explicit x, y, dimensions, color, and shape type in a static array, using a yellow-green background and semi-transparent fills. Using d3.select and data joins, the code filters the dataset by shape type and applies circle or rect attributes, such as cx, cy, r, width, and height, to draw the mixed shapes via D3 v7's selection methods.