Change the text and display of the navigation item in MS CRM 4.0

Change the text and display of the navigation item:-

var iOpps = 0;
if(document.getElementById('navOpps') != null)
{
document.getElementById('navOpps').getElementsByTagName('NOBR')[0].innerText =
document.getElementById('navOpps').getElementsByTagName('NOBR')[0].innerText + " (" + iOpps + ")";
document.getElementById('navOpps').getElementsByTagName('NOBR')[0].style.color = "#FF0000";
document.getElementById('navOpps').getElementsByTagName('NOBR')[0].style.fontWeight = "700";
}