Fiddling with colors.

resources/bionxcontrol.qss

@@ -7,6 +7,16 @@ QWidget
     font-family: Segoe UI, sans-serif;
 }
 
+QMainWindow
+{
+  background-color: #272727;
+}
+
+QSplitter
+{
+color: red;
+  background-color: #272727;
+}
 /* Spezifisches Styling für Buttons */
 QPushButton
 {
@@ -35,8 +45,8 @@ QPushButton:pressed
 
 QListView
 {
-    background-color: #f5f5f5;
-    border: none;
+    background-color: #404142;
+    border-radius: 8px;
     outline: none;
     show-decoration-selected: 0;
 }