diff --git a/book.json b/book.json
index dfaf592370f400969b7744cf6c42bfb31a0d9118..2f84e826a36c442018b85df3dc22e66cd7a0da83 100644
--- a/book.json
+++ b/book.json
@@ -9,5 +9,10 @@
     "localized-footer": {
         "hline": true,
         "filename": "FOOTER.md"
+    },
+    "pluginsConfig": {
+        "prism": {
+            "css": ["prismjs/themes/prism-okaidia.css"]
+        }
     }
 }