This example shows five semi-transparent circles of varying sizes and colors positioned across a light green background. Each circle is defined by explicit x, y, and radius values within a hardcoded data array, with a fixed opacity of 0.7 applied to all shapes. The visualization uses D3’s `select` and data join pattern to bind the array to SVG `circle` elements, setting attributes for position, size, and fill color. The SVG canvas is created with dimensions matching the container’s client width and height.