// get the window height
function getWindowHeight() {

	var windowHeight = 0;
	
	if (typeof(window.innerHeight) == 'number') {

		windowHeight = window.innerHeight;

	} else {

		if (document.documentElement && document.documentElement.clientHeight) {
			
			windowHeight = document.documentElement.clientHeight;
		
		} else {
			
			if (document.body && document.body.clientHeight) {
				windowHeight = document.body.clientHeight;
			}
			
		}
	}
	
	return windowHeight;

}



// set the footer size
function setFooter() {

	if (document.getElementById) {
		
		var windowHeight=getWindowHeight();
		
		if (windowHeight > 0) {
		
			var contentHeight = document.getElementById('all_content').offsetHeight;
			var footerElement = document.getElementById('footer');
			var footerHeight = footerElement.offsetHeight;
			
			if (windowHeight - (contentHeight+footerHeight) >= 0) {
				
				footerElement.style.position='relative';
				footerElement.style.top = (windowHeight - (contentHeight+footerHeight)) + 'px';
			
			} else {
				
				footerElement.style.position = 'static';
	
			}
		}
	}
}

window.onresize = function() {
  setFooter();
}