Fix Nav Bar Using Bootstrap with the Shadow at the Bottom

The Html Code is :
  1. <div class="navbar navbar-inverse navbar-fixed-top" id="custom-nav" role="navigation">  
  2.    <div class="navbar-header">  
  3.       <button type="button" class="navbar-toggle" data-toggle="collapse"   
  4.          data-target="#example-navbar-collapse">  
  5.          <span class="sr-only">Toggle navigation</span>  
  6.          <span class="icon-bar"></span>  
  7.          <span class="icon-bar"></span>  
  8.          <span class="icon-bar"></span>  
  9.       </button>  
  10.       <a class="navbar-brand" href="#">eService</a>  
  11.    </div>  
  12.    <div class="collapse navbar-collapse" id="example-navbar-collapse">  
  13.       <ul class="nav navbar-nav">  
  14.          <li><a href="index.html">Home</a></li>  
  15.           <li><a href="#about">About</a></li>  
  16.           <li><a href="contact.html">Contact</a></li>  
  17.           <li class="dropdown">  
  18.             <a href="#" class="dropdown-toggle" data-toggle="dropdown">  
  19.                   Services  
  20.                   <b class="caret"></b>  
  21.             </a>  
  22.             <ul class="dropdown-menu">  
  23.               <li><a href="#">Service1</a></li>  
  24.               <li><a href="#">Service2</a></li>  
  25.               <li><a href="#">Service3</a></li>  
  26.                
  27.             </ul>  
  28.           </li><!-- dropdown -->  
  29.           <li class="dropdown">  
  30.             <a href="#" class="dropdown-toggle" data-toggle="dropdown">  
  31.                   Events  
  32.                   <b class="caret"></b>  
  33.             </a>  
  34.             <ul class="dropdown-menu">  
  35.               <li><a href="#">Event1</a></li>  
  36.               <li><a href="#">Event2</a></li>  
  37.               <li><a href="#">Event3</a></li>  
  38.               <li><a href="#">Event4</a></li>  
  39.               <li><a href="#">Event5</a></li>  
  40.             </ul>  
  41.           </li><!-- dropdown -->  
  42.         </ul><!-- /.nav -->  
  43.    </div>  
  44. </div>  
The Css is 
  1. #custom-nav {  
  2.     -webkit-box-shadow: 10px 20px 20px #0072BA;  
  3.     -moz-box-shadow:    20px 20px 20px #0072BA;  
  4.     box-shadow:         20px 20px 20px #0072BA;  
  5.     z-index:999;  
  6. }  
And Last the Display output: