statemachine and styles

mainwindow.h

@@ -3,6 +3,7 @@
 
 #include <QMainWindow>
 #include <QSettings>
+#include <QStateMachine>
 
 namespace Ui {
 class MainWindow;
@@ -18,10 +19,18 @@ public:
     explicit MainWindow(QWidget *parent = nullptr);
     ~MainWindow() override;
 
+private slots:
+    void on_btn_startstop_clicked();
+
 private:
     Ui::MainWindow *ui;
 
     QSettings* mSettings = nullptr;
+    QStateMachine mState;
+    QByteArray mCss;
+
+    void initStateMachine();
+    void triggerCssUpdate();
 };
 
 }