Popmotion/popmotion ? reverse-engineered prompt

Build me a small animation library for JavaScript that feels simple to use but powerful enough for real UI work.

I want one main animate function that can drive numbers, colors, and other strings like px values, shadows, and SVG paths. It should support both smooth tween style animations and spring style motion, with sensible defaults, repeat options, delays, easing, and callbacks for update, complete, stop, play, and repeat. It should be easy to import only what I need, stay lightweight, and work cleanly in modern browsers.

Please include a few basic examples or a tiny playground so I can see it working on numbers, colors, and a more complex string. If anything in the docs is unclear, look up the current usage online and match the public API as closely as you can.