// check browser version

var isNC    = (document.layers) ? 1 : 0;

var isOPERA = (navigator.userAgent.indexOf('Opera') >= 0)? true : false;

var isIE    = (document.all && !isOPERA)? true : false;

var isDOM   = (document.getElementById && !isIE && !isOPERA)? true : false;