Better position for nav-bars close button

src/sao.less

@@ -7,6 +7,11 @@
     }
 }
 
+.nav-tabs > li .close {
+    margin: -2px 0 0 10px;
+    font-size: 18px;
+}
+
 .treeview {
     & > table.tree {
         width: 100%;