I built a zero-dependency CSS library with 9 built-in themes — here's why

I was building my tenth landing page this year. Same routine: open a new project, copy the button styles from the last one, paste the card CSS, tweak the colors, fight with Bootstrap's opinionated defaults or spend 40 minutes configuring Tailwind just to get a centered hero section. At some point I asked myself: why don't I have a single file I can drop into any project and just start building? That question turned into six months of work. The result is njX UI — a pure CSS component library built specifically for landing pages. The problem with existing options I didn't want to build yet another library. I genuinely tried to use what existed: Bootstrap — great for dashboards and admin panels. For landing pages it feels heavy (~200KB), opinionated, and every Bootstrap site looks the same unless you heavily customize it. Tailwind CSS — I actually like Tailwind. But it requires a build step, PostCSS, a config file, and you're essentially writing CSS in your HTML. For a quick landing page