nav{
  list-style-type: none;
  width: 980px;
  height: 70px;
  padding:6px 0px 0px 0px;
  clear:both;
}
nav li{
  position: relative;
  float: left;
  margin: 0;
  padding: 0;
}
nav li a{
  display: block;
  margin: 0;
  padding:0;
  line-height: 1;
  text-decoration: none;
}
nav li ul{
  list-style: none;
  position: absolute;
  left: 0;
  margin: 0;
  padding: 0;
  z-index:100;
}

nav li ul li{
  overflow: hidden;
  width: 100%;
  height: 0;
  color: #fff;
  -moz-transition: .2s;
  -webkit-transition: .2s;
  -o-transition: .2s;
  -ms-transition: .2s;
  transition: .2s;
}
nav li ul li a{
  padding: 10px;
  background-color:#fff;
  opacity:0.85;
  filter: alpha(opacity=85);/*for ie 8 */
  text-align: left;
  font-size: 12px;
  font-weight: normal;
}
nav li:hover ul li{
  overflow: visible;
  height: 30px;
  border-top: 1px solid #dcdcdc;
}
nav li:hover ul li:first-child{
  border-top: 0;
}
nav li:hover ul li:last-child{
  border-bottom: 0;
  width: 100%;
}
nav li:hover ul li:last-child a{
  border-radius: 0 0 3px 3px;
}