The prompt

Build a modular pricing configurator with Tailwind CSS. Use a max-w-4xl two-column grid. The left column is a list of six selectable module cards: each a bordered rounded-xl row with a checkbox on the left, a module name and a one-line description, and a price on the right; the core module is pre-selected and disabled with a muted "Required" label. Selected cards gain a neutral-900 border and a faint background. The right column is a sticky summary card listing the chosen modules as rows with names and prices, a bundle discount line in green that appears from three modules, a bold total, a dark checkout button and a muted note about monthly billing. Then add JavaScript that toggles modules, rebuilds the summary rows, applies a ten percent discount at three modules and fifteen at five, and updates the total and the button label with the module count.

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