dhg/Skeleton ? reverse-engineered prompt

Build me a simple responsive starter site that I can use as a clean boilerplate for other projects.

I want a very lightweight landing page with a basic HTML starting point, a small CSS file for the core styling, a reset so the page looks consistent in different browsers, and a simple grid that makes the layout adapt nicely on phones, tablets, and desktop. Keep it minimal and easy to understand, with plain HTML and vanilla CSS only. Include a few sample elements like headings, paragraphs, buttons, forms, and columns so I can see how the styles work right away.

It should feel like a dead simple foundation, not a big design system. Make sure it is easy to drop into a new project and start building from there.