var viewportwidth;
var viewportheight;

if (typeof window.innerWidth != 'undefined') {
	viewportwidth = window.innerWidth,
	viewportheight = window.innerHeight
}
else if (typeof document.documentElement != 'undefined' && 
		typeof document.documentElement.clientWidth != 'undefined' && 
		document.documentElement.clientWidth != 0) {
	viewportwidth = document.documentElement.clientWidth,
	viewportheight = document.documentElement.clientHeight
}
else {
	viewportwidth = document.getElementsByTagName('body')[0].clientWidth,
	viewportheight = document.getElementsByTagName('body')[0].clientHeight
}
window.onload = function () {
	if (document.all) {
		document.getElementById('content').style.height = viewportheight-340+'px';
	}
}