diff --git a/public/md/themes/default.css b/public/md/themes/default.css
index d5a2a312..2350e5ed 100644
--- a/public/md/themes/default.css
+++ b/public/md/themes/default.css
@@ -222,6 +222,7 @@ pre.prettyprint {
   text-align: start;
   border: 0;
   padding: 10px 20px;
+  font-size: 12px;
 }
 pre.prettyprint code {
   background-color: transparent !important;