Added TanStack Start installation guide (#2288)

This PR adds the installation guide of Tailwind CSS version 4 for
[TanStack Start](https://tanstack.com/start/latest)

Preview URL:
https://tailwindcss-com-git-fork-max-programming-ta-2b2c4f-tailwindlabs.vercel.app/docs/installation/framework-guides/tanstack-start

Let me know if any changes are required

---------

Co-authored-by: Philipp Spiess <[email protected]>

Author: max-programming

src/app/(docs)/docs/installation/framework-guides/index.ts

@@ -18,6 +18,7 @@ const guides: Guide[] = await create({
   angular: () => import("./angular"),
   "ruby-on-rails": () => import("./ruby-on-rails"),
   "react-router": () => import("./react-router"),
+  "tanstack-start": () => import("./tanstack-start"),
   phoenix: () => import("./phoenix"),
   parcel: () => import("./parcel"),
   symfony: () => import("./symfony"),

src/app/(docs)/docs/installation/framework-guides/tanstack-start.tsx

@@ -0,0 +1,147 @@
+import { css, js, Page, shell, Step, Tile } from "./utils";
+import Logo from "@/docs/img/guides/tanstack.react.svg";
+import LogoDark from "@/docs/img/guides/tanstack-white.react.svg";
+
+export let tile: Tile = {
+  title: "TanStack Start",
+  description: "Full-stack Framework powered by TanStack Router for React and Solid.",
+  Logo,
+  LogoDark,
+};
+
+export let page: Page = {
+  title: "Install Tailwind CSS with TanStack Start",
+  description: "Setting up Tailwind CSS in a TanStack Start project.",
+};
+
+export let steps: Step[] = [
+  {
+    title: "Create project",
+    body: (
+      <p>
+        Start by creating a new TanStack Start project if you don’t have one set up already. The most common approach is
+        to use <a href="https://tanstack.com/start/latest/docs/framework/react/overview">Create Start App</a>.
+      </p>
+    ),
+    code: {
+      name: "Terminal",
+      lang: "shell",
+      code: shell`
+        npx create-start-app@latest my-project
+        cd my-project
+      `,
+    },
+  },
+  {
+    title: "Install Tailwind CSS",
+    body: (
+      <p>
+        Install <code>@tailwindcss/vite</code> and its peer dependencies via npm.
+      </p>
+    ),
+    code: {
+      name: "Terminal",
+      lang: "shell",
+      code: shell`
+        npm install tailwindcss @tailwindcss/vite
+      `,
+    },
+  },
+  {
+    title: "Configure Vite Plugin",
+    body: (
+      <p>
+        Add the <code>@tailwindcss/vite</code> plugin to your Vite configuration.
+      </p>
+    ),
+    code: {
+      name: "vite.config.ts",
+      lang: "ts",
+      code: js`
+        import { tanstackStart } from '@tanstack/react-start/plugin/vite';
+        import { defineConfig } from 'vite';
+        import tsConfigPaths from 'vite-tsconfig-paths';
+        // [!code highlight:2]
+        import tailwindcss from '@tailwindcss/vite'
+
+        export default defineConfig({
+          plugins: [
+            // [!code highlight:2]
+            tailwindcss()
+            tanstackStart(),
+            tsConfigPaths(),
+          ]
+        });
+      `,
+    },
+  },
+  {
+    title: "Import Tailwind CSS",
+    body: (
+      <p>
+        Add an <code>@import</code> to <code>./src/styles.css</code> that imports Tailwind CSS.
+      </p>
+    ),
+    code: {
+      name: "src/styles.css",
+      lang: "css",
+      code: css`
+        @import "tailwindcss";
+      `,
+    },
+  },
+  {
+    title: "Import the CSS file in your root route",
+    body: (
+      <p>
+        Import the CSS file in your <code>__root.tsx</code> file with the <code>?url</code> query.
+      </p>
+    ),
+    code: {
+      name: "src/routes/__root.tsx",
+      lang: "tsx",
+      code: js`
+        // other imports...
+
+        // [!code highlight:2]
+        import appCss from '../styles.css?url'
+
+        export const Route = createRootRoute({
+          head: () => ({
+            meta: [
+              // your meta tags and site config
+            ],
+            // [!code highlight:2]
+            links: [{ rel: 'stylesheet', href: appCss }],
+            // other head config
+          }),
+          component: RootComponent,
+        })
+      `,
+    },
+  },
+  {
+    title: "Start using Tailwind in your project",
+    body: <p>Start using Tailwind’s utility classes to style your content.</p>,
+    code: {
+      name: "src/routes/index.tsx",
+      lang: "tsx",
+      code: js`
+        import { createFileRoute } from '@tanstack/react-router'
+
+        export const Route = createFileRoute('/')({
+          component: App,
+        })
+
+        function App() {
+          return (
+            // [!code highlight:4]
+            <h1 class="text-3xl font-bold underline">
+              Hello World!
+            </h1>
+          )
+        }
+      `,
+    },
+  },
+];