Radix UI
radix-ui.com
Components, icons, and colors for building high‑quality, accessible UI. Free and open-source.
Show multiple screens once, Responsive design tester
Responsive Viewer is a multi-screen responsive testing tool that allows you to test and preview your website on multiple screens with built-in screenshot and annotation tools.
Responsive Viewer provides a seamless way to preview your website on multiple screens simultaneously within an infinite canvas. You can set up a preview space that shows you multiple screens, choose from many real screen mockups available, and sync scrolling and navigation across screens.
radix-ui.com
Components, icons, and colors for building high‑quality, accessible UI. Free and open-source.
framer.com
An open source, production-ready motion library for React on the web.