KelpUI is new library that Chris Ferdinandi is developing, designed to leverage newer CSS features and Web Components.

He outlined his principles up front in a post back in April:

I’m imagining a system that includes…

• Base styles for all of the common HTML elements.
• Loads of utility classes for nudging and tweaking things.
• Group classes for styling more complex UI elements without a million little classes.
• Easy customization with CSS variables.
• Web Components to progressively add interactivity to functional HTML.
• All of the Web Component HTML lives in the light DOM, so its easy to style and reason about.

I’m imagining something that can be loaded directly from a CDN, downloaded locally, or imported if you want to roll your own build.

KelpUI is still evolving, and that’s part of the beauty of looking at it now and following Chris’s blog as he openly chronicles his approach. There’s always going to be some opinionated directions in a library like this, but I love that the guiding philosophy is so clear and is being used as a yardstick to drive decisions.