use beat hit sound as menu click confirm

src/assets.html

@@ -14,6 +14,7 @@
 <a-asset-item id="tunnelObj" src="assets/models/tunnel.obj"></a-asset-item>
 <a-asset-item id="tunnelNeonObj" src="assets/models/tunnelneon.obj"></a-asset-item>
 
+<audio id="confirmSound" src="assets/sounds/beatHit.ogg"></audio>
 <audio id="hoverSound" src="assets/sounds/hover.ogg"></audio>
 
 <img id="backglowTexture" src="assets/img/stage/backglow.png">

src/templates/gameMenu.html

@@ -21,7 +21,8 @@
   id="gameMenu"
   bind__visible="isGameOver || isPaused || isVictory"
   position="0 1.1 -2"
-  play-sound="event: mouseenter; sound: #hoverSound; volume: 0.03">
+  play-sound="event: mouseenter; sound: #hoverSound; volume: 0.03"
+  play-sound__click="event: click; sound: #confirmSound; volume: 0.25">
 
   <!-- Actions. -->
   <a-entity

src/templates/menu.html

@@ -214,6 +214,7 @@
     <a-plane
       id="playButton"
       play-sound="event: mouseenter; sound: #hoverSound; volume: 0.03"
+      play-sound__click="event: click; sound: #confirmSound; volume: 0.25"
       position="0 -0.51 0"
       proxy-event="event: click; to: a-scene; as: playbuttonclick"
       material="shader: flat; src: #playImg; transparent: true; color: #CCC"