Endless Game. Allow user to continue the game.

- main.css isn't compiled
- a special class `.tile-gold` is added to tiles above 2048

js/keyboard_input_manager.js

@@ -53,10 +53,13 @@ KeyboardInputManager.prototype.listen = function () {
     }
   });
 
-  var retry = document.getElementsByClassName("retry-button")[0];
+  var retry = document.querySelector(".retry-button");
   retry.addEventListener("click", this.restart.bind(this));
   retry.addEventListener("touchend", this.restart.bind(this));
 
+  var keepPlaying = document.querySelector(".keep-playing-button");
+  keepPlaying.addEventListener("click", this.keepPlaying.bind(this));
+
   // Listen to swipe events
   var touchStartClientX, touchStartClientY;
   var gameContainer = document.getElementsByClassName("game-container")[0];
@@ -93,3 +96,8 @@ KeyboardInputManager.prototype.restart = function (event) {
   event.preventDefault();
   this.emit("restart");
 };
+
+KeyboardInputManager.prototype.keepPlaying = function (event) {
+  event.preventDefault();
+  this.emit("keepPlaying");
+};