var mnuSelected = '';
function showMenu(menu){
hideMenu(mnuSelected);
document.getElementById(menu).style.visibility = 'visible';
mnuSelected = menu;
}
function hideMenu(menu){
if(mnuSelected!='')
document.getElementById(menu).style.visibility = 'hidden';
}
function init(){
	//center navigation menu
	if(document.all){
	aWidth = document.body.clientWidth;
	document.getElementById('menuBar').style.width = aWidth;
	}
	else{
	aWidth = innerWidth;
	document.getElementById('menuBar').style.width = aWidth-8;
	}
	//top and left positioning for navigation menu
document.getElementById('menuBar').style.width = aWidth;
document.getElementById('menuBar').style.top = 60;
document.getElementById('About').style.left = parseInt((aWidth/2 - 300));
document.getElementById('About').style.top = 60;
document.getElementById('Projects').style.left = parseInt((aWidth/2 - 200));
document.getElementById('Projects').style.top = 60;
document.getElementById('Multimedia').style.left = parseInt(aWidth/2 -100);
document.getElementById('Multimedia').style.top = 60;
document.getElementById('Links').style.left = parseInt((aWidth/2));
document.getElementById('Links').style.top = 60;
document.getElementById('Contact').style.left = parseInt((aWidth/2 + 100));
document.getElementById('Contact').style.top = 60;
document.getElementById('mnuAbout').style.left = document.getElementById('About').style.left;
document.getElementById('mnuAbout').style.top = 97;
document.getElementById('mnuProjects').style.left = document.getElementById('Projects').style.left;
document.getElementById('mnuProjects').style.top = 97;
document.getElementById('mnuMultimedia').style.left = document.getElementById('Multimedia').style.left;
document.getElementById('mnuMultimedia').style.top = 97;
document.getElementById('mnuLinks').style.left = document.getElementById('Links').style.left;
document.getElementById('mnuLinks').style.top = 97;
document.getElementById('mnuContact').style.left = document.getElementById('Contact').style.left;
document.getElementById('mnuContact').style.top = 97;
}