function init() {
	if (curNav>0) {
		// init nav
		document.getElementById('nav-but-'+curNav + '-sel').style.visibility = 'visible';
		document.getElementById('nav-but-'+curNav).style.visibility = 'hidden';		
	}
	if (curSubNav>0) {
		// init subnav
		
		document.getElementById('sub-nav-but-'+curSubNav + '-sel').style.visibility = 'visible';
		document.getElementById('sub-nav-but-'+curSubNav).style.visibility = 'hidden';
		document.getElementById('sub-nav-but-'+curSubNav + '-button').style.cursor = 'auto';
	}
}

function toggleNavButton(num) {

	if (curNav!=num) { 
	
		for (i=1;i<=numNav;i++) {
			if (i != num && i != curNav) {
				document.getElementById('nav-but-' + i + '-sel').style.visibility='hidden';
				document.getElementById('nav-but-' + i).style.visibility='visible';
			}
						
		}
	
		document.getElementById('nav-but-'+num + '-sel').style.visibility = 'visible';
		document.getElementById('nav-but-'+num).style.visibility = 'hidden';
	}
}

function deSelNavButton(num) {
	if (curNav!=num) { 
		document.getElementById('nav-but-'+num + '-sel').style.visibility = 'hidden';
		document.getElementById('nav-but-'+num).style.visibility = 'visible';
	}
}

function selNav(num) {
	curNav = num;
	curSubNav = 0;

		for (i=1;i<=numNav;i++) {
			if (i != num && i != curNav) {
				document.getElementById('nav-but-' + i + '-sel').style.visibility='hidden';
				document.getElementById('nav-but-' + i).style.visibility='visible';
			}
						
		}	

	document.getElementById('nav-but-'+num + '-sel').style.visibility = 'visible';
	document.getElementById('nav-but-'+num).style.visibility = 'hidden';

}

function toggleSubNavButton(num) {
	if (curSubNav!=num) { 
		for (i=1;i<=numSubNav;i++) {
			if (i != num && i != curSubNav) {
				document.getElementById('sub-nav-but-' + i + '-sel').style.visibility='hidden';
				document.getElementById('sub-nav-but-' + i).style.visibility='visible';
			}
						
		}
	
		document.getElementById('sub-nav-but-'+num + '-sel').style.visibility = 'visible';
		document.getElementById('sub-nav-but-'+num).style.visibility = 'hidden';
	}
}

function deSelSubNavButton(num) {
	if (curSubNav!=num) { 
		document.getElementById('sub-nav-but-'+num + '-sel').style.visibility = 'hidden';
		document.getElementById('sub-nav-but-'+num).style.visibility = 'visible';
	}
}

function goURL(url) {
	document.location=url;
}