As per the official page of Tailwind CSS, it is a highly customizable, low-level CSS framework that gives you all of the building blocks you need to build bespoke designs without any annoying opinionated styles you have to fight to override.
To simply put, Tailwind provides helper classes for almost every CSS rule available.
Fuse includes and uses Tailwind whenever it's possible. There are no traditional styles available within the Fuse, Though there are edge cases that cannot be styled using Tailwind, 99% of the Fuse is styled using Tailwind.
To use Tailwind, you don't need to do any setup as all Tailwind classes can be accessible from any HTML file you create by default.
Tailwind configuration can be found in /src/tailwind.config.js
file. This file is used to configure the generated classes by Tailwind. We already
configured the Tailwind using the config file to provide sensible defaults for a web app.
Fuse also uses Tailwind as its main configuration source for Angular Material theming. If you want to add/edit/remove any color or change the font families, you have to do that via the Tailwind's config file
Since Angular v11, Tailwind support has been added into the AngularCLI so you don't have to do anything to build Tailwind.
Official Tailwind CSS documentation: https://tailwindcss.com/