....

resources/views/layouts/site.blade.php

@@ -41,6 +41,8 @@
   <link href="{{ asset('css/app_m.css') }}" rel="stylesheet">
   @elseif (isset($user) && isset($user->profile) && $user->profile->gender == 2)
   <link href="{{ asset('css/app_f.css') }}" rel="stylesheet">
+  @elseif (isset($user) && isset($user->profile) && $user->profile->gender == 0)
+  <link href="{{ asset('css/app.css') }}" rel="stylesheet">
   @else
   <link href="{{ asset('css/app.css') }}" rel="stylesheet">
   @endif