.dropdown,.dropup{position:relative}
 .dropdown-toggle:focus{outline:0}
 .dropdown-menu{position:absolute;top:100%;left:0;z-index:1000;display:none;float:left;min-width:160px;padding:5px 0;margin:2px 0 0;font-size:14px;text-align:left;list-style:none;background-color:#fff;-webkit-background-clip:padding-box;background-clip:padding-box;border:1px solid #ccc;border:1px solid rgba(0,0,0,.15);border-radius:4px;-webkit-box-shadow:0 6px 12px rgba(0,0,0,.175);box-shadow:0 6px 12px rgba(0,0,0,.175)}
 .dropdown-menu.pull-right{right:0;left:auto}
 .dropdown-menu .divider{height:1px;margin:9px 0;overflow:hidden;background-color:#e5e5e5}
 .dropdown-menu>li>a{display:block;padding:3px 20px;clear:both;font-weight:400;line-height:1.42857143;color:#333;white-space:nowrap}
 .dropdown-menu>li>a:focus,.dropdown-menu>li>a:hover{color:#262626;text-decoration:none;background-color:#f5f5f5}
 .dropdown-menu>.active>a,.dropdown-menu>.active>a:focus,.dropdown-menu>.active>a:hover{color:#fff;text-decoration:none;background-color:#337ab7;outline:0}
 .dropdown-menu>.disabled>a,.dropdown-menu>.disabled>a:focus,.dropdown-menu>.disabled>a:hover{color:#777}
 .dropdown-menu>.disabled>a:focus,.dropdown-menu>.disabled>a:hover{text-decoration:none;cursor:not-allowed;background-color:transparent;background-image:none;filter:progid:DXImageTransform.Microsoft.gradient(enabled=false)}
 .open>.dropdown-menu{display:block}
 .open>a{outline:0}
 .dropdown-menu-right{right:0;left:auto}
 .dropdown-menu-left{right:auto;left:0}
 .dropdown-header{display:block;padding:3px 20px;font-size:12px;line-height:1.42857143;color:#777;white-space:nowrap}
 .dropdown-backdrop{position:fixed;top:0;right:0;bottom:0;left:0;z-index:990}
 .pull-right>.dropdown-menu{right:0;left:auto}
 .dropup .caret,.navbar-fixed-bottom .dropdown .caret{content:"";border-top:0;border-bottom:4px dashed;border-bottom:4px solid\9}
 .dropup .dropdown-menu,.navbar-fixed-bottom .dropdown .dropdown-menu{top:auto;bottom:100%;margin-bottom:2px}
 
/* actual dropdown animation */
.dropdown .dropdown-menu
 {
    -webkit-transition: all 0.75s;
    -moz-transition: all 0.75s;
    -ms-transition: all 0.75s;
    -o-transition: all 0.75s;
    transition: all 0.75s;

    max-height: 0;
    display: block;
    overflow: hidden;
    opacity: 0;
 }

.dropdown.open .dropdown-menu {
    max-height: 200px;
    opacity: 1;
}