Tencent/weui ? reverse-engineered prompt

Build me a mobile web UI library that feels like the official WeChat style, with clean simple components for common app screens.

I want reusable pieces like buttons, cells, dialogs, progress bars, toast messages, articles, action sheets, and icons, all looking consistent on phones and easy to drop into a page. Please make it polished, responsive, and ready for WeChat web use, with a small demo page that shows the main components working together.

Keep the design close to the familiar WeChat look, with sensible spacing, typography, and touch friendly controls. If it helps, include a basic documentation or demo area so I can quickly see how each component should be used. Use the current best practices for the styling and build setup, and look up current docs online if you need to.