[refactor] improve menu tab index and focus on open

Author: zombieFox

index.html

@@ -89,13 +89,13 @@
 
 <ulclass="menu-nav u-list-unstyled">
 <liclass="menu-nav-item">
-<buttonclass="menu-nav-button button button-block button-large active" data-target=".menu-content-area-header">Header</button>
+<buttonclass="menu-nav-button button button-block button-large active" data-target=".menu-content-area-header"tabindex="1">Header</button>
 </li>
 <liclass="menu-nav-item">
-<buttonclass="menu-nav-button button button-block button-large" data-target=".menu-content-area-bookmarks">Bookmarks</button>
+<buttonclass="menu-nav-button button button-block button-large" data-target=".menu-content-area-bookmarks"tabindex="1">Bookmarks</button>
 </li>
 <liclass="menu-nav-item">
-<buttonclass="menu-nav-button button button-block button-large" data-target=".menu-content-area-layout">Layout</button>
+<buttonclass="menu-nav-button button button-block button-large" data-target=".menu-content-area-layout"tabindex="1">Layout</button>
 </li>
 </ul>
 <divclass="menu-content">

js/menu.js

@@ -46,6 +46,7 @@ var menu = (function(){
 varhtml=helper.e("html");
 if(state.get().menu.active){
 helper.addClass(html,"is-menu-open");
+helper.e(".menu-nav-button.active").focus();
 shade.render({
 action: function(){
 close();