diff --git a/src/appearance.ui b/src/appearance.ui
index ee8f5d2..0218520 100644
--- a/src/appearance.ui
+++ b/src/appearance.ui
@@ -41,7 +41,11 @@
     </widget>
    </item>
    <item row="1" column="1">
-    <widget class="QSpinBox" name="cornerRadius"/>
+    <widget class="QSpinBox" name="cornerRadius">
+     <property name="maximum">
+      <number>16</number>
+     </property>
+    </widget>
    </item>
    <item row="2" column="0">
     <widget class="QLabel" name="label_3">