Wireframe Greybox.

A crisp greybox / blueprint lo-fi wireframe of a desktop SaaS dashboard — neutral grey blocks, image placeholders with a diagonal-cross X, lorem-bar text, a schematic chart panel, and monospace redline annotations on a 12-column grid. Use when the brief asks for "greybox", "blueprint wireframe", "lo-fi dashboard", "low fidelity", "线框图", or "灰盒原型".