Change border color detail on startpage

resources/less/metager/startpage-only.less

@@ -70,7 +70,7 @@ html {
     margin-top: -@scrollLinkHeight;
     display: flex;
     text-align: center;
-    border-top:1px solid lightgrey;
+    border-top:1px solid #888888;
     position: sticky;
     top: 0;
     z-index: 10;