diff --git a/js/reveal.js b/js/reveal.js
index 425b6174..2e3ee391 100644
--- a/js/reveal.js
+++ b/js/reveal.js
@@ -1,5 +1,5 @@
 /*!
- * reveal.js 2.1 r36
+ * reveal.js 2.1 r37
  * http://lab.hakim.se/reveal-js
  * MIT licensed
  *
@@ -1014,28 +1014,28 @@ var Reveal = (function(){
 
 	function navigateLeft() {
 		// Prioritize hiding fragments
-		if( isOverviewActive() || previousFragment() === false ) {
+		if( availableRoutes().left && ( isOverviewActive() || previousFragment() === false ) ) {
 			slide( indexh - 1, 0 );
 		}
 	}
 
 	function navigateRight() {
 		// Prioritize revealing fragments
-		if( isOverviewActive() || nextFragment() === false ) {
+		if( availableRoutes().right && ( isOverviewActive() || nextFragment() === false ) ) {
 			slide( indexh + 1, 0 );
 		}
 	}
 
 	function navigateUp() {
 		// Prioritize hiding fragments
-		if( isOverviewActive() || previousFragment() === false ) {
+		if( availableRoutes().up && ( isOverviewActive() || previousFragment() === false ) ) {
 			slide( indexh, indexv - 1 );
 		}
 	}
 
 	function navigateDown() {
 		// Prioritize revealing fragments
-		if( isOverviewActive() || nextFragment() === false ) {
+		if( availableRoutes().down && ( isOverviewActive() || nextFragment() === false ) ) {
 			slide( indexh, indexv + 1 );
 		}
 	}
@@ -1057,7 +1057,7 @@ var Reveal = (function(){
 				var previousSlide = document.querySelector( '.reveal .slides>section.past:nth-child(' + indexh + ')' );
 
 				if( previousSlide ) {
-					indexv = ( previousSlide.querySelectorAll('section').length + 1 ) || 0;
+					indexv = ( previousSlide.querySelectorAll( 'section' ).length + 1 ) || 0;
 					indexh --;
 					slide();
 				}
diff --git a/js/reveal.min.js b/js/reveal.min.js
index e389070d..53fb1290 100644
--- a/js/reveal.min.js
+++ b/js/reveal.min.js
@@ -1,5 +1,5 @@
 /*!
- * reveal.js 2.1 r36
+ * reveal.js 2.1 r37
  * http://lab.hakim.se/reveal-js
  * MIT licensed
  *
@@ -62,8 +62,8 @@ r("fragmentshown",{fragment:am[0]});return true;}}else{var al=document.querySele
 r("fragmentshown",{fragment:al[0]});return true;}}return false;}function Q(){if(document.querySelector(b+".present")){var am=document.querySelectorAll(b+".present .fragment.visible");
 if(am.length){am[am.length-1].classList.remove("visible");r("fragmenthidden",{fragment:am[am.length-1]});return true;}}else{var al=document.querySelectorAll(l+".present .fragment.visible");
 if(al.length){al[al.length-1].classList.remove("visible");r("fragmenthidden",{fragment:al[al.length-1]});return true;}}return false;}function O(){clearTimeout(k);
-if(Y){k=setTimeout(x,Y);}}function B(){if(L()||Q()===false){a(m-1,0);}}function j(){if(L()||v()===false){a(m+1,0);}}function u(){if(L()||Q()===false){a(m,e-1);
-}}function F(){if(L()||v()===false){a(m,e+1);}}function Z(){if(Q()===false){if(g().up){u();}else{var al=document.querySelector(".reveal .slides>section.past:nth-child("+m+")");
+if(Y){k=setTimeout(x,Y);}}function B(){if(g().left&&(L()||Q()===false)){a(m-1,0);}}function j(){if(g().right&&(L()||v()===false)){a(m+1,0);}}function u(){if(g().up&&(L()||Q()===false)){a(m,e-1);
+}}function F(){if(g().down&&(L()||v()===false)){a(m,e+1);}}function Z(){if(Q()===false){if(g().up){u();}else{var al=document.querySelector(".reveal .slides>section.past:nth-child("+m+")");
 if(al){e=(al.querySelectorAll("section").length+1)||0;m--;a();}}}}function x(){if(v()===false){g().down?F():j();}O();}function ah(an){var am=document.activeElement;
 var ao=!!(document.activeElement&&(document.activeElement.type||document.activeElement.href||document.activeElement.contentEditable!=="inherit"));if(ao||an.shiftKey||an.altKey||an.ctrlKey||an.metaKey){return;
 }var al=true;switch(an.keyCode){case 80:case 33:Z();break;case 78:case 34:x();break;case 72:case 37:B();break;case 76:case 39:j();break;case 75:case 38:u();