diff --git a/kcc/KCC_gui.py b/kcc/KCC_gui.py
index 50f25d0..97cb977 100644
--- a/kcc/KCC_gui.py
+++ b/kcc/KCC_gui.py
@@ -292,9 +292,9 @@ class Ui_KCC(object):
         if enable:
             if self.currentMode == 1:
                 self.modeBasic()
-            if self.currentMode == 2:
+            elif self.currentMode == 2:
                 self.modeAdvanced()
-            if self.currentMode == 3:
+            elif self.currentMode == 3:
                 self.modeExpert()
 
     def changeGamma(self, value):
diff --git a/kcc/image.py b/kcc/image.py
index 0c2ee91..c5af9b4 100755
--- a/kcc/image.py
+++ b/kcc/image.py
@@ -260,7 +260,8 @@ class ComicPage:
             diff -= delta
             pageNumberCut2 = diff
             diff += delta
-            oldStat = ImageStat.Stat(self.image.crop((0, heightImg - diff, widthImg, heightImg - pageNumberCut2))).var[0]
+            oldStat = ImageStat.Stat(self.image.crop((0, heightImg - diff, widthImg,
+                                                      heightImg - pageNumberCut2))).var[0]
             while ImageStat.Stat(self.image.crop((0, heightImg - diff, widthImg, heightImg - pageNumberCut2))).var[0]\
                     < fixedThreshold + oldStat and diff < heightImg / 4:
                 diff += delta
@@ -268,8 +269,8 @@ class ComicPage:
             pageNumberCut3 = diff
             delta = 5
             diff = delta
-            while ImageStat.Stat(self.image.crop((0, heightImg - pageNumberCut2, diff, heightImg))).var[0] < fixedThreshold\
-                    and diff < widthImg:
+            while ImageStat.Stat(self.image.crop((0, heightImg - pageNumberCut2, diff, heightImg))).var[0]\
+                    < fixedThreshold and diff < widthImg:
                 diff += delta
             diff -= delta
             pageNumberX1 = diff