Bold level 1 items in the tree

public/css/style.css

@@ -2014,6 +2014,10 @@ body.in-iframe .main-row > .sidebar {
     text-decoration: none;
     color: #333;
 }
+.note-container .note-lhs-tree>.note-tree-node>a:not([data-non-segment-target]) {
+    font-weight: bold;
+    color: #333;
+}
 .note-container .note-lhs-tree .note-tree-node>a:hover {
     background-color: aliceblue;
     color: #0d59af !important;