Update per @mit-mit review

src/content/get-dart/index.md

@@ -59,9 +59,9 @@ NOTE to editors: Keep the zip file link as the last thing in the paragraph,
 so it's easy to find (but not more tempting than package managers).
 {% endcomment %}
 
-{{site.alert.warn}}
-{% include_relative archive/_sdk-terms.md %}
-{{site.alert.end}}
+:::warning Notice
+{% include './archive/_sdk-terms.md' %}
+:::
 
 If you've installed or plan to
 [install the Flutter SDK][install-flutter],
@@ -78,13 +78,13 @@ Install the Dart SDK using the package manager for your platform.
   <li class="tab-link" data-tab="tab-sdk-install-mac">macOS</li>
 </ul>
 <div id="tab-sdk-install-windows" class="tabs__content current" markdown="1">
-{% include_relative _windows.md %}
+{% include '_windows.md' %}
 </div>
 <div id="tab-sdk-install-linux" class="tabs__content" markdown="1">
-{% include_relative _linux.md %}
+{% include '_linux.md' %}
 </div>
 <div id="tab-sdk-install-mac" class="tabs__content" markdown="1">
-{% include_relative _mac.md %}
+{% include '_mac.md' %}
 </div>
 
 ## About release channels and version strings {#release-channels}
@@ -140,4 +140,4 @@ follow the [instructions on this page](#install)
 [dl-sdk]: /get-dart/archive
 [install-flutter]: {{site.flutter-docs}}/get-started/install
 [10]: https://www.microsoft.com/en-us/software-download/windows10%20
-[11]: https://www.microsoft.com/en-us/software-download/windows11
+[11]: https://www.microsoft.com/en-us/software-download/windows11