SVG Fundamentals
This example introduces the fundamentals of SVG shapes as a foundation for D3-based visualization work. It displays primitive geometric elements—two circles, a navy line, and a red path—positioned within a minimal SVG container in an HTML document. The code uses the SVG specification directly, including `<circle>`, `<line>`, and `<path>` elements, with attributes like `cx`, `cy`, `r`, and `d` to define geometry and styling. No dynamic data or JavaScript libraries are invoked; the visualization demonstrates static markup only, serving as a starting point for understanding how D3 version 6 generates and manipulates SVG output for charts.