title: How to change button color when it takes background color?
body: <p>Here i gave screenshot of my screen and i want the entire button color to change when hovered but only borders or changing button takes background color in cente area how can i chage it </p>
  
  <p><img src="https://i.stack.imgur.com/aRCWb.png" alt=""></p>
  
  <pre><code>class window(QtGui.QMainWindow):
      def __init__(self):
          super(window,self).__init__()
          self.setGeometry(50,50,500,500)
          self.setWindowTitle("PAVAI")
          self.setStyleSheet("background-image: url(/home/balaji/black.png)")
          #self.setStyleSheet('background-color: qlineargradient(x1: 0, y1: 0, x2: 1, y2: 1,stop: 0 white, stop: 0.4 gray,stop: 1 green);')
  
  
          Calculate = QtGui.QPushButton("SHRINKAGE",self)
          Calculate.move(100,200)
          Calculate.resize(270,320)
          Calculate.setStyleSheet('QPushButton :{ background-color: red; }')
          Calculate.setStyleSheet('QPushButton:hover{ background-color: red; }')
          Calculate.clicked.connect(self.shrinkage)
  </code></pre>