/**
 * run when page is ready
 *
 * @return html string
 * @author Ethan
 **/
Ext.onReady(function(){
  Ext.select("#topnav dd").on('mouseover', switchOn);
  Ext.select("#topnav dd").on('mouseout', switchOff);
});

/**
 * top navigation effect handler
 *
 * @return html string
 * @author Ethan
 **/
function switchOn(e) {
  Ext.select('#'+e.target.id).addClass('hover');
}
function switchOff(e) {
  Ext.select('#'+e.target.id).removeClass('hover');
}