A clean sci-fi HUD theme thumbnail, precisely 218x140 resolution. Single-color design using pure white (#FFFFFF) or light cyan with varying opacities on a dark navy/black background. The layout must feature layered geometric shapes: a large central hexagonal frame, surrounded by a matrix of smaller interlocking tech-hexagons. Add tech-line accents, circuit-like paths, and nested thin hexagonal borders to create depth. Strict constraints: Flat design, sharp vector lines, use ONLY monochrome color blocks and opacity or fill-opacity / stroke-opacity for layering. NO gradients, NO images, NO text, NO numbers, NO organic shapes, NO spaceships, NO complex decorative charts. Pure geometry and high-tech scannable structure.