feat(search): highlight search result terms

Signed-off-by: Phil Kuang <pkuang@factset.com>

docs/features/search/getting-started.md

@@ -71,6 +71,7 @@ export const searchPage = (
                         <CatalogResultListItem
                           key={result.document.location}
                           result={result.document}
+                          highlight={result.highlight}
                         />
                       );
                     default:
@@ -78,6 +79,7 @@ export const searchPage = (
                         <DefaultResultListItem
                           key={result.document.location}
                           result={result.document}
+                          highlight={result.highlight}
                         />
                       );
                   }
@@ -267,6 +269,7 @@ an example:
               <CatalogResultListItem
                 key={result.document.location}
                 result={result.document}
+                highlight={result.highlight}
               />
             );
           // ...

docs/features/search/how-to-guides.md

@@ -398,6 +398,29 @@ export class YourSearchEngine implements SearchEngine {
 }
 ```
 
+## How to customize search results highlighting styling
+
+The default highlighting styling for matched terms in search results is your
+browsers default styles for the `<mark>` HTML tag. If you want to customize
+how highlighted terms look you can follow Backstage's guide on how to
+[Customize the look-and-feel of your App](https://backstage.io/docs/getting-started/app-custom-theme)
+to create an override with your preferred styling.
+
+For example, the following will result in highlighted terms to be bold & underlined:
+
+```jsx
+const highlightOverride = {
+  BackstageHighlightedSearchResultText: {
+    highlight: {
+      color: 'inherit',
+      backgroundColor: 'inherit',
+      fontWeight: 'bold',
+      textDecoration: 'underline',
+    },
+  },
+};
+```
+
 [obj-mode]: https://nodejs.org/docs/latest-v14.x/api/stream.html#stream_object_mode
 [read-stream]: https://nodejs.org/docs/latest-v14.x/api/stream.html#stream_readable_streams
 [async-gen]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for-await...of#iterating_over_async_generators