diff --git a/theme-arc-blue.css b/theme-arc-blue.css
index b2b14da..51a7c00 100644
--- a/theme-arc-blue.css
+++ b/theme-arc-blue.css
@@ -888,7 +888,7 @@
       color: #b6b6b6;
   }
   .hljs-addition {
-      background: #15217B !mportant;
+      background: #15217B !important;
       color: #bdbdbd;
   }
   .hljs-deletion {