diff --git a/doc/doxygen.css b/doc/doxygen.css
index f29d3715..9c2fc6a2 100644
--- a/doc/doxygen.css
+++ b/doc/doxygen.css
@@ -1445,3 +1445,6 @@ div.contents ul li {
     top: 50%;
     margin-top: -11px;
 }
+.arrow {
+    cursor: pointer;
+}