📝(doc) improve README

The README was a bit boring, let's add some colorful changes!

README.md

@@ -1,18 +1,94 @@
-# 🎨 Cunningham, the best OpenSource Design System
+<div align="center">
+  <a href="https://openfun.github.io/cunningham"><img src="./resources/banner.png" alt="" /></a>
+</div>
 
-[![CircleCI](https://circleci.com/gh/openfun/cunningham/tree/master.svg?style=svg)](https://circleci.com/gh/openfun/richie/tree/master)
+<div align="center">
 
-<p align="center">
-    <a href="https://openfun.github.io/cunningham"><b>📚&nbsp;&nbsp;Documentation</b></a> •
-    <a href="https://www.figma.com/file/sSEMhow3g5zpEkyDLEQ1ZO/DS-Cunningham?node-id=47%3A261&t=nKRnadK4sslyVxD7-0"><b>🖌️&nbsp;&nbsp;Figma</b></a>
-</p>
+# Cunningham
 
-## Getting started
+**A design system and a components library.**
 
-Everything is detailed on our [documentation](https://openfun.github.io/cunningham). 📚
+<a href="https://openfun.github.io/cunningham"><b>📚&nbsp;&nbsp;Documentation</b></a> •
+<a href="https://www.figma.com/file/sSEMhow3g5zpEkyDLEQ1ZO/DS-Cunningham?node-id=47%3A261&t=nKRnadK4sslyVxD7-0"><b>🖌️&nbsp;&nbsp;Figma</b></a>
+</div>
+
+- **Atomic**: We follow [atomic design principles](https://bradfrost.com/blog/post/atomic-web-design/).
+- **Modular and Reusable**: Each component is designed to be self-contained and reusable across different projects, promoting consistency and saving development time.
+- **Accessibility-focused**: Our components prioritize accessibility standards, making them usable and inclusive for all users. 
+- **Design tokens based**: We use [design tokens](https://openfun.github.io/cunningham/?path=/docs/getting-started-customization--docs#what-are-design-tokens-) to ensure consistency between design and code and allow high customization.
+- **React** based: at the moment we only support React, but we are open to other frameworks, feel free to [contribute](./CONTRIBUTING.md) !
+
+<div align="center">
+
+[![CircleCI](https://circleci.com/gh/openfun/cunningham/tree/main.svg?style=svg)](https://circleci.com/gh/openfun/cunningham/tree/main)
+
+</div>
+
+## 🔎 Preview
+
+Here are some examples of real life usage of Cunningham components.
+
+<a href="https://openfun.github.io/cunningham"><img src="./resources/examples.png" alt=""/></a>
+
+<div align="center">
+
+See the [documentation](https://openfun.github.io/cunningham) 📚 to learn more about customization, typography, spacings and available components!
+
+</div>
+
+## ⚡️ Getting started
+
+➡️ First, install the library
+
+```
+yarn add @openfun/cunningham-react
+```
+
+➡️ Then, add this script to your `package.json` file
+```json
+{
+    "scripts": {
+        "build-theme": "cunningham -g css -o src"
+    },
+}
+```
+
+➡️ Then, in order to generate the css file, run
+
+```
+yarn build-theme
+```
+
+It will generate a file named `cunningham-tokens.css`.
+
+➡️ Then, add these lines at the top of your main stylesheet file:
+
+```
+@import "@openfun/cunningham-react/fonts"; // Imports default fonts ( Roboto ). You can also import fonts by yourself.
+@import "@openfun/cunningham-react/icons"; // Imports icons ( Material Icons ).
+@import "@openfun/cunningham-react/style"; // Imports the default theme.
+@import "cunningham-tokens"; // Imports the file you just generated.
+```
+
+> Please take a look at [customization documentation](https://openfun.github.io/cunningham/?path=/docs/getting-started-customization--docs) for more informations about the `cunningham` command line tool and to customize your local theme.
+
+We're done! 🎉
+
+To ensure everything works well, let's test rendering a component, such as the [Button](https://openfun.github.io/cunningham/?path=/docs/components-button--docs) for example.
+
+Now please see the [documentation](https://openfun.github.io/cunningham) 📚 to learn more about customization, typography, spacings and available components!
+
+
+## Contributors
+
+<a href="https://github.com/openfun/cunningham/graphs/contributors">
+  <img src="https://contrib.rocks/image?repo=openfun/cunningham" />
+</a>
 
 ## Contributing
 
+This project is intended to be community-driven, so please, do not hesitate to get in touch if you have any question related to our implementation or design decisions.
+
 Please see our [contributing guidelines](./CONTRIBUTING.md).
 
 ## License