replace background empty item with null

.config/quickshell/modules/cheatsheet/Cheatsheet.qml

@@ -111,7 +111,7 @@ Scope { // Scope
                             cheatsheetRoot.hide()
                         }
 
-                        background: Item {}
+                        background: null
                         contentItem: Rectangle {
                             anchors.fill: parent
                             radius: Appearance.rounding.full

.config/quickshell/modules/common/widgets/NavRailButton.qml

@@ -16,7 +16,7 @@ Button {
     implicitHeight: columnLayout.implicitHeight
     implicitWidth: columnLayout.implicitWidth
 
-    background: Item {}
+    background: null
     PointingHandInteraction {}
 
     // Real stuff

.config/quickshell/modules/common/widgets/StyledToolTip.qml

@@ -26,7 +26,7 @@ ToolTip {
         }
     }
 
-    background: Item {}
+    background: null
     
     contentItem: Item {
         id: contentItemBackground

.config/quickshell/modules/overview/SearchWidget.qml

@@ -227,7 +227,7 @@ Item { // Wrapper
                         }
                     }
 
-                    background: Item {}
+                    background: null
 
                     cursorDelegate: Rectangle {
                         width: 1

.config/quickshell/modules/sidebarLeft/AiChat.qml

@@ -383,7 +383,7 @@ int main(int argc, char* argv[]) {
                     placeholderText: StringUtils.format(qsTr('Message the model... "{0}" for commands'), root.commandPrefix)
                     placeholderTextColor: Appearance.m3colors.m3outline
 
-                    background: Item {}
+                    background: null
 
                     onTextChanged: { // Handle suggestions
                         if(messageInputField.text.length === 0) {

.config/quickshell/modules/sidebarLeft/Anime.qml

@@ -419,7 +419,7 @@ Item {
                     placeholderText: StringUtils.format(qsTr('Enter tags, or "{0}" for commands'), root.commandPrefix)
                     placeholderTextColor: Appearance.m3colors.m3outline
 
-                    background: Item {}
+                    background: null
 
                     property Timer searchTimer: Timer { // Timer for tag suggestions
                         interval: root.tagSuggestionDelay