Pseudo Line Chart is a minimal, full-screen visualization that draws a single rounded rectangle as its primary visual element. The chart uses D3's `select` to target an SVG and dynamically sets its width and height based on the browser viewport, appending a `rect` with a corner radius of 40 pixels. The styling relies on a fixed, full-viewport body layout with hidden overflow to ensure the graphic fills the screen. No data or additional chart elements are present, making it a demonstration of basic D3 SVG manipulation and responsive sizing.