How to dynamically change the css style of the title?

[devext]

Hi friends,


How can I change the css style of the title 'PRO SERIES 1' with 'beforeexpand' ?
Thanks !

proltd1.on('beforeexpand', ????????? );

Accordion menu :

new Ext.Panel({
  renderTo:'menu-partie1',
  autoHeight: true,
  ctCls: 'menu-rubrique-principale-header',
  baseCls: 'content-accordion',
  layout: 'accordion',
    defaults: {
    bodyStyle: 'padding:0.2em'
  },
  layoutConfig: {
    titleCollapse: true,
    animate: true,
    fill: false
  },
  items:[
  proltd1 = new Ext.Panel({
      id:'proltd1',
      title: 'PRO SERIES 1',
      cls: 'menu-rubrique-principale',
      hideCollapseTool:true,
      collapsed:true,
      contentEl:'proltd0'

  }),
  proltd2 = new Ext.Panel({
      id:'proltd2',
      title: 'PRO SERIES 2',
      cls: 'menu-rubrique-principale',
      hideCollapseTool:true,
      collapsed:true,
      contentEl:'classic-series'
  })
  
 ]
});

[tryanDLS]

I would think you could inspect the rendered HTML in firebug to learn what CSS class is applied to the title element. You could add a CSS override to change it, over you could get a reference to that Element and call setStyle or addClass.