Create a square premium technology advertisement featuring an unbranded seventy-five-percent modular mechanical keyboard. Use a smoke-transparent polycarbonate case, a visible brushed brass plate, warm ivory keycaps, and one removable anodized metal control knob. Present the keyboard from a low three-quarter product angle on a dark matte surface, with a few carefully separated modules floating behind it to explain modularity without becoming an explosive diagram. Shape the transparent edges with a broad softbox, pass one narrow cool-white beam through the case, and add a restrained warm rim to the brass components. The backdrop is a graphite gradient with faint controlled haze and generous clean negative space for later campaign copy, but include no text inside the image. Every switch position, key row, screw, port, and structural joint must look intentional and manufacturable. Render realistic polycarbonate refraction, fine metal brushing, subtle fingerprints, and grounded contact shadow. No brand marks, no fake logos, no watermark, no repeated keys, no warped layout, and no melted plastic appearance.