src/gui/dictionary_tool/win_aero_style.qss

QToolBar > .QPushButton {
  background-color: rgba(213,228,246,60%);
  border-color: rgba(183,196,225,60%);
  color: rgba(16,16,64,90%);
  border-width: 1px;
  border-style: solid;
  border-radius: 5px;
  min-height: 16px;
  min-width: 50px;
  padding: 2px;
}

QToolBar > .QPushButton:pressed {
  background-color: rgba(221,228,235,80%);
  border-style: solid;
  border-width: 1px;
  padding-left: 6px;
  padding-top: 6px;
}

QToolBar > .QPushButton:hover {
  border-width: 1px;
  border-style: solid;
  background-color: rgba(238,243,250,80%);
}

QToolBar > .QPushButton:disabled {
  background-color: rgba(211,220,230,60%);
  color: rgb(96,100,104);
}

QToolBar > .QPushButton::menu-indicator {
  subcontrol-position: right center;
  subcontrol-origin: padding;
  left: -2px;
}

QToolBar {
 border-width: 0px;
 margin: 0px;
 padding: 5px;
 spacing: 5px;
}