fix: list code block copy button config

exampleSite/content/docs/guide/syntax-highlighting.md

@@ -78,12 +78,10 @@ def main():
     say_hello()
 ```
 
-
 ### Copy Button
 
 By default, copy button is enabled for code blocks.
 
-
 ## Supported Languages
 
 For a list of supported languages, please see the [Chroma documentation](https://github.com/alecthomas/chroma#supported-languages).

exampleSite/hugo.yaml

@@ -151,6 +151,12 @@ params:
       sortBy: date
       sortOrder: desc # or "asc"
 
+  highlight:
+    copy:
+      enable: true
+      # hover | always
+      display: hover
+
   comments:
     enable: false
     type: giscus