This piece reproduces Sol LeWitt’s Wall Drawing #370 in inverted form, displaying a grid of thin colored rectangles over a central square void. The code builds the scene using SVG, creating two masks: the first hides a horizontal set of 100 bars inside a square, the second reveals vertical bars outside it. Both mask patterns are generated procedurally via JavaScript and the DOM API, with each rectangle sized relative to the browser window, producing the final inverted checkerboard effect.