This example demonstrates basic geometric shapes rendered as scalable vector graphics: a red circle, a green rect, a thick black line, and a polygonal path composed of straight segments. The shapes are drawn directly in an SVG element within the HTML, with styling applied through inline attributes such as `fill`, `stroke`, and `stroke-width`. The accompanying CSS sets the page margins and overflow, while all visual properties for the shapes are defined using native SVG presentation attributes rather than a JavaScript library.