A full-screen SVG displays 100 horizontal stripes alternating in height across the viewport, with a circular mask revealing only the central region. The mask is defined as an SVG `<mask>` containing a white rectangle and a black circle, applied to each stripe via the `mask` attribute. The visualization uses raw DOM manipulation with `document.createElementNS` and `setAttribute` to construct the SVG elements dynamically in JavaScript, without any external libraries.