The prompt

Build a split markdown editor with Tailwind CSS. Use a bordered rounded-2xl card with a toolbar holding a document title on the left, a word and character count in the middle, and on the right a two-option segmented control for Split and Preview plus a small "Copy HTML" button. Below, a two-column grid: the left pane is a monospaced textarea on a faint background with no border and a comfortable line height, pre-filled with a short sample document; the right pane is the rendered output on white with sensible typographic spacing. Then add JavaScript implementing a small markdown renderer covering headings up to level three, bold, italic, inline code, links, unordered lists, blockquotes and fenced code blocks, escaping HTML first so pasted markup cannot inject; re-render on input with a short debounce, keep the counts current, switch layout when Preview is selected, and copy the generated HTML.

Paste it into Claude, Cursor, v0 or any AI coding tool. Prefer the finished markup? Open the Tailwind source.