/*----事例一 折叠式菜单，适合放在左边，做菜单树------*/

/*左侧菜单*/
.sidebar-menu {
    border-right: 1px solid #c4c8cb;
}
/*一级菜单*/
.menu-first {
    height: 45px;
    line-height: 45px;
    background-color: #e9e9e9;
    border-top: 1px solid #efefef;
    border-bottom: 1px solid #e1e1e1;
    padding: 0;
    font-size: 14px;
    font-weight: normal;
    text-align: center;
}
    /*一级菜单鼠标划过状态*/
    .menu-first:hover {
        text-decoration: none;
        background-color: #d6d4d5;
        border-top: 1px solid #b7b7b7;
        border-bottom: 1px solid #acacac;
    }
/*二级菜单*/
.menu-second li a {
    background-color: #f6f6f6;
    height: 31px;
    line-height: 31px;
    border-top: 1px solid #efefef;
    border-bottom: 1px solid #efefef;
    font-size: 12px;
    text-align: center;
}
    /*二级菜单鼠标划过样式*/
    .menu-second li a:hover {
        text-decoration: none;
        background-color: #66c3ec;
        border-top: 1px solid #83ceed;
        border-bottom: 1px solid #83ceed;
        border-right: 3px solid #f8881c;
        border-left: 3px solid #66c3ec;
    }
/*二级菜单选中状态*/
.menu-second-selected {
    background-color: #66c3ec;
    height: 31px;
    line-height: 31px;
    border-top: 1px solid #83ceed;
    border-bottom: 1px solid #83ceed;
    border-right: 3px solid #f8881c;
    border-left: 3px solid #66c3ec;
    text-align: center;
}
/*覆盖bootstrap的样式*/
.nav-list, .nav-list li a {
    padding: 0px;
    margin: 0px;
}

/*
<div class="sidebar-menu">
    <a href="#userMeun" class="nav-header menu-first collapsed" data-toggle="collapse"><i class="icon-user-md icon-large"></i> 用户管理</a>
    <ul id="userMeun" class="nav nav-list collapse menu-second">
        <li><a href="#"><i class="icon-user"></i> 增加用户</a></li>
        <li><a href="#"><i class="icon-edit"></i> 修改用户</a></li>
        <li><a href="#"><i class="icon-trash"></i> 删除用户</a></li>
        <li><a href="#"><i class="icon-list"></i> 用户列表</a></li>
 
    </ul>
    <a href="#articleMenu" class="nav-header menu-first collapsed" data-toggle="collapse"><i class="icon-book icon-large"></i> 文章管理</a>
    <ul id="articleMenu" class="nav nav-list collapse menu-second">
        <li><a href="#"><i class="icon-pencil"></i> 添加文章</a></li>
        <li><a href="#"><i class="icon-list-alt"></i> 文章列表</a></li>
    </ul>
</div>*/


/*----事例二 真正的多级菜单(子菜单显示在右边，容易超出边框) ------*/

.dropdown-submenu {
    position: relative;
}

    .dropdown-submenu > .dropdown-menu {
        top: 0;
        left: 100%;
        margin-top: -6px;
        margin-left: -1px;
        -webkit-border-radius: 0 6px 6px 6px;
        -moz-border-radius: 0 6px 6px;
        border-radius: 0 6px 6px 6px;
    }

    .dropdown-submenu:hover > .dropdown-menu {
        display: block;
    }

    .dropdown-submenu > a:after {
        display: block;
        content: " ";
        float: right;
        width: 0;
        height: 0;
        border-color: transparent;
        border-style: solid;
        border-width: 5px 0 5px 5px;
        border-left-color: #ccc;
        margin-top: 5px;
        margin-right: -10px;
    }

    .dropdown-submenu:hover > a:after {
        border-left-color: #fff;
    }

    .dropdown-submenu.pull-left {
        float: none;
    }

        .dropdown-submenu.pull-left > .dropdown-menu {
            left: -100%;
            margin-left: 10px;
            -webkit-border-radius: 6px 0 6px 6px;
            -moz-border-radius: 6px 0 6px 6px;
            border-radius: 6px 0 6px 6px;
        }
/*
<div class="container">  
    <div class="row">  
        <h2>Bootstrap 3多级下拉菜单</h2>  
        <hr>  
        <div class="dropdown">  
            <a id="dLabel" role="button" data-toggle="dropdown" class="btn btn-primary" data-target="#"  
               href="javascript:;">  
                下拉多级菜单 <span class="caret"></span>  
            </a>  
            <ul class="dropdown-menu multi-level" role="menu" aria-labelledby="dropdownMenu">  
                <li><a href="javascript:;">一级菜单</a></li>  
                <li><a href="javascript:;">一级菜单</a></li>  
                <li class="divider"></li>  
                <li class="dropdown-submenu">  
                    <a tabindex="-1" href="javascript:;">一级菜单</a>  
                    <ul class="dropdown-menu">  
                        <li><a tabindex="-1" href="javascript:;">二级菜单</a></li>  
                        <li class="divider"></li>  
                        <li class="dropdown-submenu">  
                            <a href="javascript:;">二级菜单</a>  
                            <ul class="dropdown-menu">  
                                <li><a href="javascript:;">三级菜单</a></li>  
                            </ul>  
                        </li>  
                    </ul>  
                </li>  
            </ul>  
        </div>  
    </div>  
</div>  */