kcms/nightcolor: make description look like the one in the User Feedback KCM

kcms/nightcolor/package/contents/ui/main.qml

@@ -73,13 +73,10 @@ KCM.SimpleKCM {
         spacing: 0
 
         QQC2.Label {
-            Layout.topMargin: Kirigami.Units.largeSpacing * 2
-            Layout.bottomMargin: Kirigami.Units.largeSpacing * 4
-            Layout.leftMargin: Kirigami.Units.smallSpacing
-            Layout.rightMargin: Kirigami.Units.smallSpacing
+            Layout.margins: Kirigami.Units.gridUnit
             Layout.alignment: Qt.AlignHCenter
-            Layout.maximumWidth: Math.round(root.width * 0.5)
 
+            Layout.maximumWidth: Math.round(root.width - (Kirigami.Units.gridUnit * 2))
             text: i18n("Night Color makes the colors on the screen warmer to reduce eye strain at the time of your choosing.")
             wrapMode: Text.WordWrap
         }