docs(www): add callout for tailwind v3

Author: shadcn

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

@@ -3,6 +3,11 @@ title: Astro
 description: Install and configure shadcn/ui for Astro
 ---
 
+<Callout className="bg-blue-50 border-blue-600 dark:border-blue-900 dark:bg-blue-950 mb-6 [&_code]:bg-blue-100 dark:[&_code]:bg-blue-900">
+  **Note:** The following guide is for Tailwind v4. If you are using Tailwind
+  v3, use `shadcn@2.3.0`.
+</Callout>
+
 <Steps>
 
 ### Create project

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

@@ -3,6 +3,11 @@ title: Laravel
 description: Install and configure shadcn/ui for Laravel
 ---
 
+<Callout className="bg-blue-50 border-blue-600 dark:border-blue-900 dark:bg-blue-950 mb-6 [&_code]:bg-blue-100 dark:[&_code]:bg-blue-900">
+  **Note:** The following guide is for Tailwind v4. If you are using Tailwind
+  v3, use `shadcn@2.3.0`.
+</Callout>
+
 <Steps>
 
 ### Create project

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

@@ -3,6 +3,11 @@ title: Next.js
 description: Install and configure shadcn/ui for Next.js.
 ---
 
+<Callout className="bg-blue-50 border-blue-600 dark:border-blue-900 dark:bg-blue-950 mb-6 [&_code]:bg-blue-100 dark:[&_code]:bg-blue-900">
+  **Note:** The following guide is for Tailwind v4. If you are using Tailwind
+  v3, use `shadcn@2.3.0`.
+</Callout>
+
 <Steps>
 
 ### Create project

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

@@ -3,6 +3,11 @@ title: Remix
 description: Install and configure shadcn/ui for Remix.
 ---
 
+<Callout className="bg-blue-50 border-blue-600 dark:border-blue-900 dark:bg-blue-950 mb-6 [&_code]:bg-blue-100 dark:[&_code]:bg-blue-900">
+  **Note:** The following guide is for Tailwind v4. If you are using Tailwind
+  v3, use `shadcn@2.3.0`.
+</Callout>
+
 <Callout>
 
 **Note:** This guide is for Remix. For React Router, see the [React Router](/docs/installation/react-router) guide.

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

@@ -3,6 +3,11 @@ title: Vite
 description: Install and configure shadcn/ui for Vite.
 ---
 
+<Callout className="bg-blue-50 border-blue-600 dark:border-blue-900 dark:bg-blue-950 mb-6 [&_code]:bg-blue-100 dark:[&_code]:bg-blue-900">
+  **Note:** The following guide is for Tailwind v4. If you are using Tailwind
+  v3, use `shadcn@2.3.0`.
+</Callout>
+
 <Steps>
 
 ### Create project