Six semi-transparent colored squares of varying sizes are scattered across a light green background, positioned with slight overlaps to create a layered composition. The visualization uses D3 v7’s selection and data-join methods (`select`, `selectAll`, `data`, `join`) to bind a static array of objects containing `x`, `y`, `width`, `height`, and `fill` properties to SVG `rect` elements. Each rectangle is centered on its coordinates by subtracting half its dimensions, and rendered with 70% opacity. The SVG canvas fills the viewport via a fixed container.