This animated SVG reproduces the geometric style of artist Sol LeWitt using strips of vertical rectangles. Two circular masks, one inverted, move diagonally across the canvas while their radii pulse between 200 and 100 pixels. The animation is created entirely with native SVG elements, including `<mask>`, `<circle>`, and `<animate>` tags, which drive the motion of the mask centers along viewport-perimeter paths. The code constructs roughly one hundred rectangular bars via a repeated loop, with each rect filtered through the masks to reveal shifting patterned compositions.