diff --git a/resources.whatwg.org/standard.css b/resources.whatwg.org/standard.css
index ffedd88ad..c91a8fb30 100644
--- a/resources.whatwg.org/standard.css
+++ b/resources.whatwg.org/standard.css
@@ -443,9 +443,6 @@ pre > code.idl, pre.idl {
 pre > code.css, pre.highlight.lang-css {
   background: #FFE;
 }
-pre > code.css::first-line { /* Special HTML-specific rule for UA stylesheet @namespace lines */
-  color: #AAAA50;
-}
 
 @media (max-width: 767px) {
   pre > code.idl, pre.idl, pre > code.css, pre.highlight.lang-css {