.dropdown-menu {
    min-width: 100px;
}
.dropdown-menu>li>a:focus, .dropdown-menu>li>a:hover{
    background:#ddd;
}
/*导航*/
.fixed-navbar-bottom{height:50px}
.fixed-navbar-bottom .navbar-bottom{position:fixed;height:50px;width:100%;left:0;bottom:0;z-index:999;line-height:50px;text-align:center;background:#fff;box-shadow:0 0 2px #000}
.navbar-bottom .nb-item{float:left;width:25%}
.nb-item a img,.nb-item a b{font-weight:normal;vertical-align:middle}