var browser = '';
var bVersion = 0;
var topHeight = 300;
var bgImgW = 1280;
var bgImgH = 850;
var bgAspect = bgImgW / bgImgH;
var bgimg;
var mid;
var footer;
var spacerBottom;

function initResize()
{
	var userAgent = navigator.userAgent;
	if (userAgent.match(/.*Chrome.*/))
	{
		browser = 'chrome';
		bVersion = parseFloat(/.*Chrome\/(\d+\.?\d*).*/.exec(userAgent)[1]);
	}
	else if (userAgent.match(/.*Firefox.*/))
	{
		browser = 'firefox';
		bVersion = parseFloat(/.*Firefox\/(\d+\.?\d*).*/.exec(userAgent)[1]);
	}
	else if (userAgent.match(/.*Safari.*/))
	{
		browser = 'safari';
		bVersion = parseFloat(/.*Version\/(\d+\.?\d*).*/.exec(userAgent)[1]);
	}
	else if (userAgent.match(/.*Opera.*/))
		browser = 'opera';
	else if (userAgent.match(/.*MSIE.*/))
	{
		browser = 'ie';
		bVersion = parseFloat(/.*MSIE (\d+\.?\d*).*/.exec(userAgent)[1]);
	}
	else
		browser = 'unknown';

	bgImg        = document.getElementById('bgimg');
	mid          = document.getElementById('mid');
	footer       = document.getElementById('footer');
	spacerBottom = document.getElementById('spacerbottom');

	window.onresize = resize;
	resize();
	document.getElementById('bgcontainer').style.display = 'block';
}

function resize()
{
	var cltW, cltH, mainH;

	if (browser != 'ie')
	{
		cltW = window.innerWidth;
		cltH = window.innerHeight;
	}
	else if (bVersion > 6)
	{
		cltW = document.documentElement.clientWidth;
		cltH = document.documentElement.clientHeight;
	}
	else
	{
		cltW = document.body.clientWidth;
		cltH = document.body.clientHeight;
	}
	mainH = topHeight + mid.offsetHeight + footer.offsetHeight;

	if (cltW < bgImgW && cltH < bgImgH)
	{
		bgImg.style.width = bgImgW + "px";
		bgImg.style.height = bgImgH + "px";
	}
	else
	{
		if ((cltW / cltH) < bgAspect)
		{
			bgImg.style.width = (cltH * bgAspect) + "px";
			bgImg.style.height = cltH + "px";
		}
		else
		{
			bgImg.style.width = cltW + "px";
			bgImg.style.height = (cltW / bgAspect) + "px";
		}
	}
	if (cltH > mainH)
		spacerBottom.style.height = (cltH - mainH) + "px";
	else
		spacerBottom.style.height = '0';
}