http://www.red-team-design.com/wp-content/uploads/2012/04/interactive-menu-with-css3-jquery-preview.png
demo

HTML

Код:
<link rel="stylesheet" href="http://forumstatic.ru/files/0011/8c/a9/84432.css">	
	<script src="http://code.jquery.com/jquery-1.7.1.min.js"></script>
<script src="http://forumstatic.ru/files/0011/8c/a9/74074.js"></script>
<ul class="menu">
    <li tabindex="1">
      <span class="title">One</span> 
      <div class="content">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse interdum dictum scelerisque. Morbi eu euismod lorem.</div>
    </li>
    <li tabindex="1">
      <span class="title">Two</span> 
      <div class="content">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse interdum dictum scelerisque. Morbi eu euismod lorem.</div>
    </li>
    <li tabindex="1">
      <span class="title">Three</span> 
      <div class="content">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse interdum dictum scelerisque. Morbi eu euismod lorem.</div>
    </li>
    <li tabindex="1">
      <span class="title">Four</span> 
      <div class="content">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse interdum dictum scelerisque. Morbi eu euismod lorem.</div>
    </li>
    <li tabindex="1">
      <span class="title">Five</span> 
      <div class="content">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse interdum dictum scelerisque. Morbi eu euismod lorem.</div>
    </li>
    <li tabindex="1">
      <span class="title">Six</span> 
      <div class="content">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse interdum dictum scelerisque. Morbi eu euismod lorem.</div>
    </li>
    <li tabindex="1"> 
      <span class="title">Seven</span>
      <div class="content">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse interdum dictum scelerisque. Morbi eu euismod lorem.</div>
    </li>
    <li tabindex="1"> 
      <span class="title">Eight</span>
      <div class="content">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse interdum dictum scelerisque. Morbi eu euismod lorem.</div>
    </li>
    <li tabindex="1"> 
      <span class="title">Nine</span>
      <div class="content">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse interdum dictum scelerisque. Morbi eu euismod lorem.</div>
    </li>     
  </ul>
  
  

	<script>
	  (function(){
	  
    // Append a close trigger for each block
    $('.menu .content').append('<span class="close">x</span>');    
    // Show window
    function showContent(elem){
    	hideContent();
    	elem.find('.content').addClass('expanded');
    	elem.addClass('cover');	
    }
    // Reset all
    function hideContent(){
    	$('.menu .content').removeClass('expanded');
    	$('.menu li').removeClass('cover');    
    }
    
    // When a li is clicked, show its content window and position it above all
    $('.menu li').click(function() {
    	showContent($(this));
    });    
    // When tabbing, show its content window using ENTER key
    $('.menu li').keypress(function(e) {
    	if (e.keyCode == 13) { 
        showContent($(this));
    	}
    });

    // When right upper close element is clicked  - reset all
    $('.menu .close').click(function(e) {
    	e.stopPropagation();
    	hideContent();
    });    
    // Also, when ESC key is pressed - reset all
    $(document).keyup(function(e) {
    	if (e.keyCode == 27) { 
    	  hideContent();
    	}
    });
    
	  })();
	</script>

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