Plugin: card_game: Fix issue preventing puzzle to reappear after hiding it

Add function doc

plugin/card_game/resources/js/cardgame.js

@@ -6,12 +6,15 @@ $(document).ready(function($){
 	} else {
 		$('.sidebar .panel-body .img-circle').parent().parent().after('<div class="enjoy-cardgame-active" onClick="installCardView()" ></div>');
 	}
-	
-	
 });
 
+/**
+ * This function inserts the <article> element 'home-card' for the card game
+ * before the .page-content element on the page (the right side of the
+ * "my courses" page) only if the element with id 'home-card' does not exist
+ * yet.
+ */
 function installCardView(){
-	
 	if (!document.getElementById("home-card")) {
 		var mess1 = $("#cardgamemessage").html();
 		var h = '<article id="home-card" style="border:solid 1px gray;" >';
@@ -58,7 +61,7 @@ function installCardView(){
 		$('.page-content').before(h);
 		
 	} else {
-		$('#home-card').fadeOut();
+		$('#home-card').fadeToggle();
 	}
 	
 }
@@ -168,6 +171,9 @@ function randomOpenCardView(){
 	}
 }
 
+/**
+ * This function changes the visibility of blocks inside the puzzle area
+ */
 function onlyOpenCardView(){
 	
 	installCardView();