diff --git a/src/Settings.php b/src/Settings.php
index 5ba0767..dacdb13 100644
--- a/src/Settings.php
+++ b/src/Settings.php
@@ -16,7 +16,10 @@ class Settings extends Collection
 
     public function __construct ($file = null, $format = false)
     {
-        $this->format = $format ? $format : pathinfo($file, PATHINFO_EXTENSION);
+        $fileFormat = ['theme' => 'json'];
+        $extname = pathinfo($file, PATHINFO_EXTENSION);
+
+        $this->format = $format ? $format : Arr::get($fileFormat, $extname, $extname);
         $this->file = $file;
     }