window.onload = function init(){
	document.getElementById('main').style.height = hoogte() + "px";
}

function hoogte(){

	if (self.innerHeight){ // Alle browsers behalve IE
		hoogte = self.innerHeight;
	} else if (document.documentElement && document.documentElement.clientHeight){ // IE6 Strict Mode
		hoogte = document.documentElement.clientHeight;
	} else if (document.body){ // Alle andere browsers
		hoogte = document.body.clientHeight;
	}	

	return hoogte;
}

function hide(id) {
	document.getElementById(id).style.display = "none";
	document.getElementById(id).style.visibility = "hidden";
}
function show(id) {
	document.getElementById(id).style.display = "";
	document.getElementById(id).style.visibility = "visible";
}
function toggle(id) {
	document.getElementById(id).style.display = (document.getElementById(id).style.display != 'none' ? 'none' : '' );
	document.getElementById(id).style.visibility = (document.getElementById(id).style.display != 'hidden' ? 'hidden' : 'visible' );
}