SO affix collapsed menu

HTML

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<script src="https://netdna.bootstrapcdn.com/twitter-bootstrap/2.3.1/js/bootstrap.min.js"></script>
<div class="container-narrow">
       <div class="container">
            <div class="header row">
                <div class="span12">
                  
                    <div class="navbar navbar-fixed-top" id="top-nav">
                        <div class="navbar-inner">
                            <a class="btn btn-navbar" data-toggle="collapse" data-target=".nav-collapse">
                                <span class="icon-bar"></span>
                                <span class="icon-bar"></span>
                                <span class="icon-bar"></span>
                            </a>
                           <h1><a class="brand" href="index.html">Logo</a></h1>
                            <div class="nav-collapse collapse affix span12 pull-right">
                                <ul class="nav pull-right">
                                    	                             
                                        <li><a href="#section-2">Cv</a></li>
                                   
                                        <li><a href="#section-3">Referancer</a></li>
                                   
                                        <li><a href="#section-4">Kontakt</a></li>
                                        
                                        <li><a href="blog.html" class="external">Blog</a></li>
                                    
                                </ul>
                            </div>
                        </div>
                    </div>
                </div>
            </div>
        </div>
     </div>

  
</div> <!-- //container narrow -->
      <hr>
	<div class="full-jumbo">
      <div class="container-narrow">
      	<div class="jumbotron">
        <div class="row">
        <div class="span3"></div>
        <div...

CSS

@import url("http://netdna.bootstrapcdn.com/twitter-bootstrap/2.3.1/css/bootstrap-combined.min.css");

/* ----------- css from page head ---------- */
body {
        padding-top: 20px;
        padding-bottom: 40px;
      }

      /* Custom container */
      .container-narrow {
        margin: 0 auto;
        max-width: 940px;
      }
   

      /* Main marketing message and sign up button */
      .jumbotron {
        margin: 60px 0;
        text-align: center;
      }
      .jumbotron h1 {
        font-size: 72px;
        line-height: 1;
      }
      .jumbotron .btn {
        font-size: 21px;
        padding: 14px 24px;
      }

      /* Supporting marketing content */
      .marketing {
        margin: 60px 0;
      }
      .marketing p + h4 {
        margin-top: 28px;
      }
	  
	  .masthead {
 		background: #F6D565;
 		
      }

/* ----------- css from main.css ---------- */


/* ==========================================================================
   Author's custom styles
   ========================================================================== */

#section-1 {
	
	
}

#section-2 {
	
	
}

#section-3 {
	
	
}

#section-4 {

	
}


#section-5 {
	
	
}

#section-6 {
	
	
}

#section-7 {
	;
	
}

.full-1 {
	background-color:#303;
	background-image:url(../images/bg.png);
	
}

.full-2 {
	background-color:#303;
	background-image:url(../images/bg1.png);
	
}

.full-3 {
	background-color:#303;
	background-image:url(../images/bg.png);
	
}

.full-4 {
	background-color:#303;
	background-image:url(../images/bg1.png);
	
}

.full-5 {
	background-color:#303;
	background-image:url(../images/bg.png);
	
}


.full-jumbo {
	
	
	
}

.navbar-inner {
    min-height: 40px;
    padding-right: 20px;
    padding-left: 20px;
    background-color: #fff !important;
    background-image: none;
    background-repeat: none;
    border: 0;
    border-radius: 0;
    box-shadow: none !important;
}


.header a.brand {
    display: inline-block;
    text-indent: -9999px;
    width: 280px;
 ...