bootstrap dropdown menu active class

i am trying to create a nav bar by using bootstrap but when I redirect active class to dropdown menu, all the sub menus receive active class. I only want Project section to use active class

<nav class="navbar navbar-default" role="navigation">
        <div class="navbar-header">
            <button type="button" class="navbar-toggle" data-toggle="collapse" 
                 data-target="#example-navbar-collapse">
                 <span class="sr-only"></span>
                 <span class="icon-bar"></span>
                 <span class="icon-bar"></span>
                 <span class="icon-bar"></span>
            </button>
        </div>
        <div class="collapse navbar-collapse" id="example-navbar-collapse">
          <ul class="nav navbar-nav">
             <li><a href="index.html">About</a></li>
             <li class="dropdown active">
                <a href="#" class="dropdown-toggle" data-toggle="dropdown">
                   Project <b class="caret"></b>
                </a>
                <ul class="dropdown-menu">
                   <li><a href="project.html">AAAA</a></li>
                   <li><a href="#">BBB</a></li>
                   <li><a href="#">CCC</a></li>
                   <li><a href="#">DDD</a></li>
                </ul>
             </li>
             <li><a href="team.html">Team</a></li>
             <li><a href="contact.html">Contact</a></li>
          </ul>
       </div>
    </nav>