diff --git a/core/css/styles.css b/core/css/styles.css
index 1a4a4ab4f3..aefc0ff755 100644
--- a/core/css/styles.css
+++ b/core/css/styles.css
@@ -178,6 +178,8 @@ input[type="checkbox"] + label:before {
 	opacity: 0.7;
 }
 
+input[type="checkbox"]:disabled +label:before { opacity: .6; }
+
 input[type="checkbox"].u-left +label:before { float: left; }
 
 input[type="checkbox"].white + label:before {