window.addEvent( 'domready', function() {

	var $body = window.document.body;
	
	var $siteBgOpacity = $( 'site-bg-opacity' );
	
	var resizeBg = (function() {
	
		var scrollSize = window.getScrollSize();
			
		$siteBgOpacity.setStyles({
			width: window.getSize().x,
			height: scrollSize.y
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	});
	
	resizeBg();
	
	window.addEvent( 'resize', function() {
	
		resizeBg();
	
	});

});