Update components/banner.mdx

Author: mintlify[bot]

components/banner.mdx

@@ -0,0 +1,67 @@
+---
+title: 'Banner'
+description: 'Use banners to display important site-wide announcements and notifications'
+icon: 'megaphone'
+---
+
+Use banners to display important announcements, updates, or notifications across your entire documentation site. Banners appear at the top of every page and support Markdown formatting.
+
+## Configuration
+
+Add a banner to your `docs.json` file. The banner supports Markdown formatting and can be made dismissible:
+
+```json
+{
+  "banner": {
+    "content": "🚀 **New feature released!** [Check out our latest updates](/changelog)",
+    "dismissible": true
+  }
+}
+```
+
+When `dismissible` is `true`, users can close the banner and it won't reappear for their session.
+
+## Examples
+
+<Tabs>
+  <Tab title="Product announcements">
+    ```json
+    {
+      "banner": {
+        "content": "🚀 Version 2.0 is now live! [See what's new](/changelog)",
+        "dismissible": true
+      }
+    }
+    ```
+  </Tab>
+  <Tab title="Maintenance notices">
+    ```json
+    {
+      "banner": {
+        "content": "⚠️ Scheduled maintenance: API will be unavailable Dec 15, 2-4 AM UTC",
+        "dismissible": false
+      }
+    }
+    ```
+  </Tab>
+  <Tab title="Migration alerts">
+    ```json
+    {
+      "banner": {
+        "content": "📋 **Action required:** Migrate to our new API by Jan 1st. [Migration guide](/migration)",
+        "dismissible": true
+      }
+    }
+    ```
+  </Tab>
+</Tabs>
+
+## Properties
+
+<ResponseField name="content" type="string" required>
+  The banner message. Supports plain text and Markdown formatting including links, bold text, and emojis.
+</ResponseField>
+
+<ResponseField name="dismissible" type="boolean">
+  Whether users can dismiss the banner. When `true`, users can close the banner and it won't reappear for their session. Defaults to `false`.
+</ResponseField>