add themes page and rounded corners card

Author: devalog

fern/products/docs/docs.yml

@@ -141,6 +141,8 @@ navigation:
   - section: Customization
     collapsed: true
     contents:
+      - page: Themes
+        path: ./pages/customization/themes.mdx
       - page: Announcement banner
         path: ./pages/navigation/announcement-banner.mdx
       - page: Changelogs

fern/products/docs/pages/customization/rounded-corners-theme.png

@@ -0,0 +1,26 @@
+---
+title: Themes
+subtitle: Pre-built visual styles for your documentation site
+---
+
+<Card 
+    title="Rounded corners" 
+    src="rounded-corners-theme.png"
+    imagePosition="top"
+    href="https://github.com/fern-demo/rounded-corners-theme"
+    imageHeight="90%"
+>
+    Features rounded UI components and a nature/water color palette. Applies `backdrop-filter` blur to Cards, Buttons, and other navigation elements for a frosted glass appearance. 
+
+    <p className="text-(color:--grayscale-a11) font-bold mt-2 flex items-center gap-1">
+      Use this template
+
+      <img src="https://files.buildwithfern.com/fern.docs.buildwithfern.com/learn/2025-09-30T17:39:54.370Z/products/home/pages/images/arrow-right-black.svg" alt="Arrow right light" className="arrow-right dark:hidden m-0 h-4 w-4" noZoom={false} />
+
+      <img src="https://files.buildwithfern.com/fern.docs.buildwithfern.com/learn/2025-09-30T17:39:54.370Z/products/home/pages/images/arrow-right-white.svg" alt="Arrow right light" className="arrow-right hidden dark:block m-0 h-4 w-4" />
+    </p>
+</Card>
+
+
+
+

fern/products/docs/pages/customization/themes.mdx

@@ -138,6 +138,11 @@ In this guide, we'll show you how to get started with Fern in under 5 minutes.
       ```
     </Accordion>
     <Accordion title='Brand your docs'>
+
+      <Note>
+        For pre-built visual styles, explore [all Fern documentation themes](/docs/customization/themes).
+      </Note>
+
       All of the branding for your docs can be configured in the `docs.yml` file.
 
       For example, to set the logos, colors, and fonts for your docs, you can