ns4 = (document.layers) ? true:false 
ie4 = (document.all) ? true:false 
ng5 = (document.getElementById) ? true:false 

function hideSec() { 
if (ng5) document.getElementById('sec1').style.visibility = "hidden" 
else if (ns4) document.sec1.visibility = "hide" 
else if (ie4) sec1.style.visibility ="hidden" 

if (ng5) document.getElementById('sec2').style.visibility = "hidden" 
else if (ns4) document.sec1.visibility = "hide" 
else if (ie4) sec1.style.visibility ="hidden" 

if (ng5) document.getElementById('sec3').style.visibility = "hidden" 
else if (ns4) document.sec1.visibility = "hide" 
else if (ie4) sec1.style.visibility ="hidden" 

if (ng5) document.getElementById('sec4').style.visibility = "hidden" 
else if (ns4) document.sec1.visibility = "hide" 
else if (ie4) sec1.style.visibility ="hidden" 

if (ng5) document.getElementById('sec5').style.visibility = "hidden" 
else if (ns4) document.sec1.visibility = "hide" 
else if (ie4) sec1.style.visibility ="hidden" 

if (ng5) document.getElementById('sec6').style.visibility = "hidden" 
else if (ns4) document.sec1.visibility = "hide" 
else if (ie4) sec1.style.visibility ="hidden" 

}

function showSec(n) { 
hideSec(); 
if (ng5) document.getElementById('sec' + n).style.visibility = "visible"; 
else if (ns4) document.layers["sec" + n].visibility = "show"; 
else if (ie4) document.all["sec" + n].style.visibility = "visible"; 
}