Five hundred glowing dots scatter across a dark, square SVG canvas. Each dot consists of a larger outer circle filled with a cyan radial gradient and a smaller, brighter white inner circle created using SVG `radialGradient` definitions. A plain `for` loop generates the dots at random positions within a fixed boundary, using D3 v4 to append `circle` elements and apply CSS classes for styling. The result is a dense, luminous field of varied-sized orbs against a near-black background.