What is CSS?
Cascading Style Sheets — the language for styling HTML, controlling layout, color, typography, and animation.
CSS describes how HTML elements should look. Selectors (`.button`, `#nav`, `h1`) target elements; properties (color, font-size, margin, display) apply styles. The cascade — the rules for which style wins when multiple apply — is what gives CSS its name. Modern CSS includes flexbox, grid, custom properties (variables), container queries, and `@layer`. Tailwind CSS is a utility-first approach: instead of writing CSS classes by hand, you compose Tailwind utility classes (`bg-blue-500`, `flex`, `gap-4`) inline. InBuild generates and exports Tailwind-based sites.