Why is styling not applied after load?

Why is styling not applied after load?

I am a jQuery novice having problems using load.
I basically want to develop an Ajax app with all the pages loaded dynamically.
The loaded html is not styled properly the way it is if I hard code the exact same html, in fact not really styled at all (see code below).

Any advice on what I am omitting or doing wrong would be appreciated

Here is the index.html...

<!doctype html>
<html lang="en">
<head>
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="pragma" content="no-cache">

  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>PPLadder</title>
    

</head>
<body>
<div data-role="page" id="somecontent"> </div>

 <script type="text/javascript" src = "js/tapp.js"></script>
</body>
</html>




tapp.js...

$(document).ready(function(){

   //Logic goes here
   var main = $("#main");
 console.log("About to show menu");
  
 $("#somecontent").load("menu1.html");
$("#somecontent").enhanceWithin();
})



menu1.html...

<div data-role="header">
    <h1>PP Ladder</h1>
  </div>
  <div data-role="main" class="ui-content" >
   <button id="login" class="ui-state-default ui-corner-all" onclick="show_login_form()" >Login</button>
  </div>