diff --git a/core/modules/system/css/system.theme.css b/core/modules/system/css/system.theme.css
index 4e83886..d02cfe4 100644
--- a/core/modules/system/css/system.theme.css
+++ b/core/modules/system/css/system.theme.css
@@ -99,6 +99,13 @@ abbr.form-required, abbr.tabledrag-changed, abbr.ajax-changed {
   margin-left: 0;
   margin-right: 0;
 }
+fieldset.no-box {
+  border: none;
+  padding: 0;
+}
+fieldset.no-box legend {
+  text-transform: none;
+}
 
 /**
  * Inline items.