Try SVG
This example demonstrates a single red rounded rectangle rendered inside an SVG element with a black border. The page uses basic HTML structure, with CSS styling targeting the SVG by ID and the rectangle by element type. The SVG markup defines the shape with x, y, width, height, and rounded corner radii, while CSS applies fill color, stroke, stroke-width, and opacity. The rect is purely static, showing SVG’s native vector drawing capabilities without any JavaScript libraries or data sources; the styling shows how CSS can control SVG presentation attributes.