Add coloring to sub-row

style.css

@@ -1271,6 +1271,11 @@ body.forum table.board-display {
 	table-layout: fixed;
 }
 
+body.forum table.board-display tr.sub-row {
+	background: var(--forum-sub);
+	border: var(--forum-sub-border);
+}
+
 body.forum table.board-display th,
 body.forum table.board-display td {
 	padding: 4px;