Display block for navbar masthead (fixes nav display on large devices)

ckanext/odsh/assets/odsh_header.css

 /* css for header */
 
+.navbar.navbar-static-top.masthead {
+  display: block;
+}
+
 /* same width as schleswig-holstein.de */
 .navbar-static-top .container {
   max-width: 960px;