Add theme key in ENV

.env.example

@@ -1,6 +1,7 @@
 APP_ENV=production
 APP_DEBUG=false
 APP_KEY=SomeRandomString3232RandomString
+APP_THEME=default
 
 DB_HOST=localhost
 DB_PORT=3306

config/themes.php

@@ -4,7 +4,7 @@ return [
     'enabled' => true,
     'themes_path' => realpath(base_path('resources/themes')),
     'asset_not_found' => 'LOG_ERROR',
-    'active' => 'default',
+    'active' => ENV('APP_THEME', 'default'),
 
     'themes' => [
         'default' => [