request fullscreen on documentElement instead of body (#1621 #1624)

css/reveal.css

@@ -47,12 +47,6 @@ body {
   background-color: #fff;
   color: #000; }
 
-html:-webkit-full-screen-ancestor {
-  background-color: inherit; }
-
-html:-moz-full-screen-ancestor {
-  background-color: inherit; }
-
 /*********************************************
  * VIEW FRAGMENTS
  *********************************************/

css/reveal.scss

@@ -57,15 +57,6 @@ body {
 	color: #000;
 }
 
-// Ensures that the main background color matches the
-// theme in fullscreen mode
-html:-webkit-full-screen-ancestor {
-	background-color: inherit;
-}
-html:-moz-full-screen-ancestor {
-	background-color: inherit;
-}
-
 
 /*********************************************
  * VIEW FRAGMENTS

js/reveal.js

@@ -1995,10 +1995,10 @@
 	 */
 	function enterFullscreen() {
 
-		var element = document.body;
+		var element = document.documentElement;
 
 		// Check which implementation is available
-		var requestMethod = element.requestFullScreen ||
+		var requestMethod = element.requestFullscreen ||
 							element.webkitRequestFullscreen ||
 							element.webkitRequestFullScreen ||
 							element.mozRequestFullScreen ||