ahsquared · December 15, 2015 23:49
diff --git a/Detect Document Width and Height b/Detect Document Width and Height
 function docElem(property) {
    var t;
    return ((t = document.documentElement) || (t = document.body.parentNode)) && t[property] ? t : document.body;
 }

 // View width and height excluding any visible scrollbars
 // http://www.highdots.com/forums/javascript/faq-topic-how-do-i-296669.html
 //    1) document.client[Width|Height] always reliable when available, including Safari2
 //    2) document.documentElement.client[Width|Height] reliable in standards mode DOCTYPE, except for Safari2, Opera<9.5
 //    3) document.body.client[Width|Height] is gives correct result when #2 does not, except for Safari2
 //    4) When document.documentElement.client[Width|Height] is unreliable, it will be size of <html> element either greater or less than desired view size
 //       https://bugzilla.mozilla.org/show_bug.cgi?id=156388#c7
 //    5) When document.body.client[Width|Height] is unreliable, it will be size of <body> element less than desired view size
 function viewSize() {
    // This algorithm avoids creating test page to determine if document.documentElement.client[Width|Height] is greater then view size,
    // will succeed where such test page wouldn't detect dynamic unreliability,
    // and will only fail in the case the right or bottom edge is within the width of a scrollbar from edge of the viewport that has visible scrollbar(s).
    var doc = docElem('clientWidth'),
        body = document.body,
        w, h;
    return document.clientWidth ? { w: document.clientWidth, h: document.clientHeight} :
        doc === body
            || (w = Math.max(doc.clientWidth, body.clientWidth)) > self.innerWidth
                || (h = Math.max(doc.clientHeight, body.clientHeight)) > self.innerHeight ? { w: body.clientWidth, h: body.clientHeight} :
            { w: w, h: h };
 }
	function docElem(property) {
	var t;
	return ((t = document.documentElement) \|\| (t = document.body.parentNode)) && t[property] ? t : document.body;
	}

	// View width and height excluding any visible scrollbars
	// http://www.highdots.com/forums/javascript/faq-topic-how-do-i-296669.html
	// 1) document.client[Width\|Height] always reliable when available, including Safari2
	// 2) document.documentElement.client[Width\|Height] reliable in standards mode DOCTYPE, except for Safari2, Opera<9.5
	// 3) document.body.client[Width\|Height] is gives correct result when #2 does not, except for Safari2
	// 4) When document.documentElement.client[Width\|Height] is unreliable, it will be size of <html> element either greater or less than desired view size
	// https://bugzilla.mozilla.org/show_bug.cgi?id=156388#c7
	// 5) When document.body.client[Width\|Height] is unreliable, it will be size of <body> element less than desired view size
	function viewSize() {
	// This algorithm avoids creating test page to determine if document.documentElement.client[Width\|Height] is greater then view size,
	// will succeed where such test page wouldn't detect dynamic unreliability,
	// and will only fail in the case the right or bottom edge is within the width of a scrollbar from edge of the viewport that has visible scrollbar(s).
	var doc = docElem('clientWidth'),
	body = document.body,
	w, h;
	return document.clientWidth ? { w: document.clientWidth, h: document.clientHeight} :
	doc === body
	\|\| (w = Math.max(doc.clientWidth, body.clientWidth)) > self.innerWidth
	\|\| (h = Math.max(doc.clientHeight, body.clientHeight)) > self.innerHeight ? { w: body.clientWidth, h: body.clientHeight} :
	{ w: w, h: h };
	}