# Concepts

> Combine classes, define variants, and resolve conflicting utilities.

## Documentation

- [Variants](https://hulla.dev/docs/style/variants.md): Define named style choices and infer their TypeScript types.
- [Composition](https://hulla.dev/docs/style/composition.md): Join class names and add conditional styles with cn().
- [Custom merging](https://hulla.dev/docs/style/custom-merging.md): Resolve conflicting Tailwind classes with a custom composer.