add examples (#513)

Author: dks333

settings/global.mdx

@@ -26,7 +26,9 @@ Every documentation site requires a `docs.json` file that contains the core conf
 ### Customization
 
 <ResponseField name="theme" type='"mint" | "maple" | "palm"' required>
-  The layout theme of the project
+  The layout theme of the project. Examples:
+    [Maple](https://maple.mintlify.app/),
+    [Palm](https://palm.mintlify.app/),
 </ResponseField>
 
 <ResponseField name="name" type="string" required>