導航欄會在'col-xs-4'類內下面走到

我在我的html頁面頂部有一個固定橫幅。當我向下滾動時，這個想法是讓身體在頂部的橫幅下面走。導航欄會在'col-xs-4'類內下面走到

除了'col-xs-4'類中的圖標以外，它能正常工作。圖標（或者我曾經放在col-xs-4類中的東西）似乎會穿過頂部的橫幅。

我怎樣才能更新這個橫幅總是在最上面。

這裏是鏈接codepen

下面

是html代碼：

<html> 

     <head> 
      <title>hello</title> 

      <meta charset="utf-8"> 
      <meta name="viewport" content="width=device-width, initial-scale=1"> 
      <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css"> 
      <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js"></script> 
      <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script> 

      <link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet"> 
     <style> 

     .navbar { 
    padding-top: 15px; 
    padding-bottom: 15px; 
    border: 0; 
    border-radius: 0; 
    margin-bottom: 0; 
    font-size: 12px; 
    letter-spacing: 5px; 
    position:fixed; 
    width:100%; 
    background-color:white; 
} 


.container-fluid { 
    padding-top: 70px; 
    padding-bottom: 70px; 
} 

     </style> 

     </head> 

     <body id="top"> 


      <nav class="navbar navbar-default"> 
       <div class="container"> 
        <div class="navbar-header myNavbar"> 
         <a class="navbar-brand" href="#top">HOME</a> 
         <button type="button" class="navbar-toggle" data-toggle="collapse" data-target="#mainNavBar"> 
          <span class="icon-bar"></span> 
          <span class="icon-bar"></span> 
          <span class="icon-bar"></span> 
         </button> 
        </div> 
        <div class="collapse navbar-collapse myNavbar" id="mainNavBar"> 
         <ul class="nav navbar-nav navbar-right"> 
          <li><a href="#about">ABOUT</a> 
          </li> 
          <li><a href="#connect">CONNECT</a> 
          </li> 
          <li><a href="#projects">PROJECTS</a> 
          </li> 
         </ul> 
        </div> 
       </div> 
      </nav> 



      <div class="container-fluid bg-1 text-center"> 
       <h3>hello world</h3> 
       <h3 style="color:lightblue;">say something...</h3> 
      </div> 

      <div id="connect"> 
       <div class="container-fluid bg-3 text-center"> 
        <h3>Connect</h3> 

        <div class="row"> 
         <div class="col-xs-4"> 
          <p> 
           <a href="#" id="linkedIn" target="_blank" class="social-btn"><i class="fa fa-linkedin fa-lg"></i></a> 
          </p> 
         </div> 
         <div class="col-xs-4"> 
          <p> 
           <a href="#" id="github" target="_blank" class="social-btn"><i class="fa fa-github fa-lg"></i></a> 
          </p> 
         </div> 
         <div class="col-xs-4"> 
          <p> 
           <a href="#" id="stackOverflow" target="_blank" class="social-btn"><i class="fa fa-stack-overflow fa-lg"></i></a> 
          </p> 
         </div> 
        </div> 

        <div class="row"> 
         <div class="col-xs-4"> 
          <p> 
           <a href="#" id="instagram" target="_blank" class="social-btn"><i class="fa fa-instagram fa-lg"></i></a> 
          </p> 
         </div> 
         <div class="col-xs-4"> 
          <p> 
           <a href="#" id="medium" target="_blank" class="social-btn"><i class="fa fa-medium fa-lg"></i></a> 
          </p> 
         </div> 
         <div class="col-xs-4"> 
          <p> 
           <a href="#" id="codepen" target="_blank" class="social-btn"><i class="fa fa-codepen fa-lg"></i></a> 
          </p> 
         </div> 
        </div> 


       </div> 
      </div> 

<br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br> 

     </body> 

     </html>

來源

2017-08-16 psj01