diff --git a/src/loss.py b/src/loss.py
index 520d350..56869df 100644
--- a/src/loss.py
+++ b/src/loss.py
@@ -78,7 +78,7 @@ def forward(self, bottom, top):
 
     def backward(self, top, propagate_down, bottom):
 
-	    # get the sign
+        # get the sign
         diff_sign = np.sign(self.diff)
 
         for i in range(2):