// JavaScript Document
last_tab = 'tab1';
function show(layerName) { 
document.getElementById(layerName).style.display = '';
} 

function hide(layerName) { 
document.getElementById(layerName).style.display = 'none';
} 
function show_next(tab_name, tot) {
document.getElementById(tab_name).className = 'tab';
var curr = document.getElementById(last_tab);
curr.className='tab_hover';
for(i=1; i<=tot; i++){
	hide('tab'+i+'_data');
}
show(tab_name+'_data');
last_tab=tab_name;
}