$(document).ready(function() {
	if(!$.browser.msie && false){
		$('#header').css('backgroundPosition', '50% 50%');
		$('#header_lines').css('backgroundPosition', '50% 50%');
		animateLines();
		animateHeader();
	}
});

var start = 50; // %
var range = 5;	// +- %
var time = 2500; //ms
function animateLines() {
	$('#header_lines').animate({
			backgroundPosition: '('+(start+randomXToY(-range, range))+'% '+(start+randomXToY(-range, range))+'%)'
		},
		time,
		'linear',
		animateLines
	);
}
function animateHeader(){
	$('#header').animate({
			backgroundPosition: '('+(start+randomXToY(-range, range))+'% '+(start+randomXToY(-range, range))+'%)'
		},
		time,
		'linear',
		animateHeader
	);
}

function randomXToY(minVal,maxVal,floatVal) {
	var randVal = minVal+(Math.random()*(maxVal-minVal));
	return typeof floatVal=='undefined'?Math.round(randVal):randVal.toFixed(floatVal);
}