Docs: update vite installation docs (#4741)

* docs: update vite installation docs

* Update content config

---------

Co-authored-by: shadcn <[email protected]>

apps/www/content/docs/installation/vite.mdx

@@ -23,6 +23,32 @@ npm install -D tailwindcss postcss autoprefixer
 npx tailwindcss init -p
 ```
 
+Add this import header in your main css file, `src/index.css` in our case:
+
+```css {1-3} showLineNumbers
+@tailwind base;
+@tailwind components;
+@tailwind utilities;
+
+/* ... */
+```
+
+Configure the tailwind template paths in `tailwind.config.js`:
+
+```js {3}
+/** @type {import('tailwindcss').Config} */
+module.exports = {
+  content: [
+    "./src/**/*.{ts,tsx,js,jsx}",
+    "./index.html"
+  ],
+  theme: {
+    extend: {},
+  },
+  plugins: [],
+}
+```
+
 ### Edit tsconfig.json file
 
 The current version of Vite splits TypeScript configuration into three files, two of which need to be edited.