title: Change color of certain tab of QToolBox
body: <p>I want to change a color of certain tab (page) of <code>QToolBox</code> like this</p>
  
  <p><a href="https://i.stack.imgur.com/oMGHY.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/oMGHY.png" alt="enter image description here"></a></p>
  
  <p>I figured out how to change a style of every tabs independently like this (StyleSheet):</p>
  
  <pre><code>        QToolBox::tab {
              background: blue;
              border-radius: 5px;
              color: black;
          }
  </code></pre>
  
  <p>Also I know how to change a palette of each <code>QWidget</code> (via <a href="https://doc.qt.io/qt-5/qwidget.html#palette-prop" rel="nofollow noreferrer"><code>setPalette</code></a> or StyleSheet like suggested <a href="https://stackoverflow.com/questions/25567624/change-stylesheet-of-qtoolbox-in-qt">here</a>). But it changes only body of certain tab, it doesn't affect the head of tab. </p>
  
  <p>So, I can not figure out how to change a certain tab. Probably there is some <a href="https://doc.qt.io/qt-5/qwidget.html#paintEvent" rel="nofollow noreferrer"><code>paintEvent()</code></a> or <a href="https://doc.qt.io/qt-5/qwidget.html#tabletEvent" rel="nofollow noreferrer"><code>tabletEvent()</code></a> but I still don't understand how to work with it.</p>