This example renders a single black-outlined bar with rounded bottom corners in an SVG. A path is constructed manually using D3 v5’s `select` and `append` methods, with coordinates and corner radii defined as variables. The path’s `d` attribute uses arc commands and conditional logic to determine the rounding direction based on height sign. The bar is drawn with no fill, displaying only its stroke. The code also includes examples of ES6 module imports and local CSS styling.