Prompt it

Create a polished responsive dashboard using semantic HTML and dependency-free CSS. Include an aside with a clearly labelled navigation menu, a main landmark with a page heading and action button, a section of three stat or metric cards, and a recent-activity section. Use CSS Grid for the desktop shell and card layout. At narrow widths, stack the sidebar above the main content and keep every control usable at 320px. Use real headings, links, button elements, visible keyboard focus styles, readable colour contrast, and sensible spacing with clamp(). Do not use JavaScript, frameworks, icon libraries, external fonts, or remote assets. Avoid unnecessary motion; if any animation or transition is added, include a reduced motion fallback with prefers-reduced-motion. Return complete copy-ready HTML and CSS, then briefly explain the grid and responsive breakpoint for a beginner.