css:#newnav{
width: 100%; height: 45px; line-height: 45px; background: url(../images/nav_bg.jpg) 0 0 repeat-x; margin-top:30px; }.main-menu { width:1200px; margin:0 auto; position: relative; font-family: Arial, sans-serif; -webkit-transition: all 300ms ease; -ms-transition: all 300ms ease; -o-transition: all 300ms ease; -moz-transition: all 300ms ease; transition: all 300ms ease;}.main-menu .navbar-collapse { padding: 0px;}.main-menu .navigation { position: relative; margin: 0px;}.main-menu .navigation>li { width: 130px; text-align: center; display: inline-block; padding: 0px 0px;}.main-menu .navigation>li>a { position: relative; display: block; font-size:14px; color: #fff; line-height: 45px; text-transform: uppercase; letter-spacing: 0px; opacity: 1; border-radius: 2px; transition: all 500ms ease; -moz-transition: all 500ms ease; -webkit-transition: all 500ms ease; -ms-transition: all 500ms ease; -o-transition: all 500ms ease;}.main-menu .navigation>li:hover>a,.main-menu .navigation>li.current>a,.main-menu .navigation>li.current-menu-item>a { color: #2078c2; background: url(../images/tilte_bg.jpg) 0 45px;}.main-menu .navigation>li>ul { position: absolute; width: 130px; padding: 0px; z-index: 100; display: none; background: #ffffff; border-top: 3px solid #2078c2; transition: all 300ms ease; -moz-transition: all 300ms ease; -webkit-transition: all 500ms ease; -ms-transition: all 300ms ease; -o-transition: all 300ms ease; -webkit-box-shadow: 2px 2px 5px 1px rgba(0, 0, 0, 0.05), -2px 0px 5px 1px rgba(0, 0, 0, 0.05); -ms-box-shadow: 2px 2px 5px 1px rgba(0, 0, 0, 0.05), -2px 0px 5px 1px rgba(0, 0, 0, 0.05); -o-box-shadow: 2px 2px 5px 1px rgba(0, 0, 0, 0.05), -2px 0px 5px 1px rgba(0, 0, 0, 0.05); -moz-box-shadow: 2px 2px 5px 1px rgba(0, 0, 0, 0.05), -2px 0px 5px 1px rgba(0, 0, 0, 0.05); box-shadow: 2px 2px 5px 1px rgba(0, 0, 0, 0.05), -2px 0px 5px 1px rgba(0, 0, 0, 0.05);}.main-menu .navigation>li>ul>li { position: relative; width: 100%; border-bottom: 1px solid rgba(0, 0, 0, 0.10);}.main-menu .navigation>li>ul>li:last-child { border-bottom: none;}.main-menu .navigation>li>ul>li>a { position: relative; display: block; line-height: 40px; font-weight: 100; font-size: 13px; text-transform: capitalize; color: #272727; transition: all 500ms ease; -moz-transition: all 500ms ease; -webkit-transition: all 500ms ease; -ms-transition: all 500ms ease; -o-transition: all 500ms ease;}.main-menu .navigation>li>ul>li:hover>a,.main-menu .navigation>li>ul>li.current>a { color: #2078c2; background: url(../images/tilte_bg.jpg) 0 45px;}.main-menu .navigation>li>ul>li>ul>li { position: relative; width: 100%; border-bottom: 1px solid #2078c2;}.main-menu .navigation>li>ul>li>ul>li:last-child { border-bottom: none;}.main-menu .navigation>li>ul>li>ul>li>a { position: relative; display: block; padding: 5px 8px; line-height: 24px; font-weight: 100; font-size: 12px; text-transform: capitalize; color: #272727; transition: all 500ms ease; -moz-transition: all 500ms ease; -webkit-transition: all 500ms ease; -ms-transition: all 500ms ease; -o-transition: all 500ms ease;}.main-menu .navigation>li.dropdown:hover>ul { visibility: visible; opacity: 1; top: 100%;}.main-menu .navigation li>ul>li.dropdown:hover>ul { visibility: visible; opacity: 1; top: 0; transition: all 300ms ease; -moz-transition: all 300ms ease; -webkit-transition: all 500ms ease; -ms-transition: all 300ms ease; -o-transition: all 300ms ease;}.main-menu .navigation>li>ul,.main-menu .navigation>li>ul>li>ul { display: block !important; visibility: hidden; opacity: 0;}<div id="newnav"> <div class="auto-container"> <div class="nav-outer clearfix"> <!-- Main Menu:头部导航 --> <nav class="main-menu"> <div class="navbar-collapse collapse clearfix"> <ul class="navigation clearfix"> <li navid="Home"> <a href="">11</a> </li> <li class="dropdown"> <a href="">22</a> <ul> <li class="dropdown"> <!--二级导航--> <a href="">222</a> </li> <li class="dropdown"> <a href="">222</a> </li> <li class="dropdown"> <a href="">222</a> </li> </ul> </li> <li class="dropdown"> <a href="">33</a> <ul> <li class="dropdown"> <a href="">333</a> </li> <li class="dropdown"> <a href="">333</a> </li> </ul> </li> <li class="dropdown"> <a href="">44</a> <ul> <li class="dropdown"> <a href="">444</a> </li> <li class="dropdown"> <a href="">444</a> </li> </ul> </li> </ul> </div> </nav> </div> </div> </div>