diff --git a/core/themes/seven/css/base/elements.css b/core/themes/seven/css/base/elements.css
index 6273177..073d17a 100644
--- a/core/themes/seven/css/base/elements.css
+++ b/core/themes/seven/css/base/elements.css
@@ -160,3 +160,9 @@ details summary {
   padding-top: 0.5em;
   padding-bottom: 0.5em;
 }
+details summary:focus {
+  border-top: 3px solid #0074bd;
+  outline: none;
+  color: #0074bd;
+  margin-top: -3px;
+}