.nav_dh{width:100%; margin: 0px auto; }
ul {margin:0px; padding:0px; list-style: none; }
ul.dropdown {position: relative; width: 100%; }
ul.dropdown li {width:180px; font-weight: bold; float: left; position: relative; background: #ecf0f1; margin-right:1px; }
ul.dropdown li a {display:block; padding:10px 8px; color: #34495e; position:relative; z-index: 2000; text-align:center; font-size:16px; font-weight:300; }
ul.dropdown li a:hover, ul.dropdown li a.hover { background:#17b7a6; position:relative; color: #fff; }
ul.dropdown li .sub_a_hover{background:#17b7a6; position:relative; color: #fff; }
ul.dropdown ul { display: none; position: absolute; top: 0; left: 0; width: 180px; z-index: 1000; }
ul.dropdown ul li { font-weight: normal; background: #f6f6f6; color: #000; border-top:1px solid #fff; }
ul.dropdown ul li a { display: block; color:#34495e !important; background: #eee !important; }
ul.dropdown ul li a:hover { display: block; background: #17b7a6 !important; color: #fff !important; }
.drop > a { position: relative; }
.drop > a:after { content: ""; position: absolute; right: 10px; top: 40%; border-left: 5px solid transparent; border-top: 5px solid #333; border-right: 5px solid transparent; z-index:9999; }
.drop > a:hover:after { content: ""; border-left: 5px solid transparent; border-top: 5px solid #fff; border-right: 5px solid transparent; }
.drop > a:after .sub_a_hover {content: ""; border-left: 5px solid transparent; border-top: 5px solid #fff; border-right: 5px solid transparent; }