var resizeTimeout;

function checkHeight() {
	var winHeight = document.documentElement.clientHeight;
	
	if (winHeight == 0) {
		winHeight = window.innerHeight;
	}
	
	clearTimeout(resizeTimeout);
	
	if (winHeight < 600) {
		if (document.getElementById('main').style.top!='300px') {
			//resizeTimeout = setTimeout("document.getElementById('main').style.top='300px'; document.body.style.background=\"url('images/background.jpg') center 0px no-repeat\";",100);
			resizeTimeout = setTimeout("document.getElementById('main').style.top='300px';",100);
		} 
	} else {
		if (document.getElementById('main').style.top!='50%') {
			//resizeTimeout = setTimeout("document.getElementById('main').style.top='50%'; document.body.style.background=\"url('images/background.jpg') center center no-repeat fixed\";",100);
			resizeTimeout = setTimeout("document.getElementById('main').style.top='50%';",100);
		}
	}
	
}