What is `nuxt.config.ts` used for?

nuxt.config.ts is the central configuration file for a Nuxt.js application. It is written in TypeScript and allows you to configure virtually every aspect of the framework: registering modules (e.g., @nuxtjs/tailwindcss), setting runtime config for environment variables, defining head metadata (title, meta tags), configuring Vite or Webpack options, enabling experimental features, adding CSS files, configuring the Nitro server, and setting up i18n. The config is strongly typed, providing auto-completion in your editor.