* {
      margin: 0;
      padding: 0;
    }
    a {
      line-break: normal;
      text-decoration: none;
    }
    ul li {
      list-style: none;
    }
    .nav {
      width: 100%;
      height: 42px;
      background: url("/images/nav-back.jpg");
    }
    .nav ul {
      width: 1200px;
      height: 100%;
      margin: auto;
      text-align: center;
    }
    .nav ul  li {
      display: inline-block;
      height: 42px;
      position: relative;
      text-align: center;
    }
    .nav ul  li::after {
      width: 0;
      height: 0;
      content: '';
      position: absolute;
      bottom: 2px;
      left: 0;
      right: 0;
      margin: auto;
      display: none;
      border-width: 6px;
      border-style: solid;
      border-color: transparent transparent #ffffff transparent;
    }
    .nav ul  li:hover::after {
      display: block;
    }
    
    .nav ul  li > a {
      color: #ffffcc;
      height: 100%;
      display: block;
      line-height: 45px;
      font-size: 16px;
      font-weight: bolder;
      padding: 0 20px;
    }
    .nav ul  li > a:hover{
      text-decoration: none;
    }
    .nav ul  li:hover > a {
      color: #cccccc;
      background: url("/images/active-nav-bac.jpg");
    }
    .nav ul  li.active > a {
      color: #cccccc;
      background: url("/images/active-nav-bac.jpg");
    }
    .nav ul  li > .pop-box {
      width: 160px;
      position: absolute;
      top: 42px;
      left: 0;
      border: 1px solid #cccccc;
      text-align: left;
      display: none;
      background: #ffffff;
    }
    .nav ul  li > .pop-box > a {
      display: block;
      height: 35px;
      line-height: 30px;
      font-size: 14px;
      padding: 0 10px;
    }
    .nav ul  li > .pop-box > a:hover {
      color: #cccccc;
      background: url("/images/active-nav-bac.jpg");
    }
    .nav ul  li:hover .pop-box {
      display: block;
    }