使用纯css打开/向上的下拉菜单

Question

我创建了一个带有纯CSS的下拉菜单，我已经把它带到了一个我喜欢的地方，除了我希望它是“drop-up”而不是“drop-down”，因为菜单栏正在进行布局的底部。我需要添加或更改以使其“下拉”？

#menu * { 
  padding:0; 
  margin: 0; 
  font: 12px georgia; 
  list-style-type:none;
}
#menu { 
  margin-top: 100px;
  float: left;
  line-height: 10px; 
  left: 200px;
}
#menu a { 
  display: block; 
  text-decoration: none; 
  color: #3B5330;
}
#menu a:hover { background: #B0BD97;}
#menu ul li ul li a:hover { 
  background: #ECF1E7; 
  padding-left:9px;
  border-left: solid 1px #000;
}
#menu ul li ul li {
  width: 140px; 
  border: none; 
  color: #B0BD97;  
  padding-top: 3px; 
  padding-bottom:3px; 
  padding-left: 3px; 
  padding-right: 3px; 
  background: #B0BD97;
}
#menu ul li ul li a { 
  font: 11px arial; 
  font-weight:normal; 
  font-variant: small-caps; 
  padding-top:3px; 
  padding-bottom:3px;
}
#menu ul li {
  float: left; 
  width: 146px; 
  font-weight: bold; 
  border-top: solid 1px #283923; 
  border-bottom: solid 1px #283923; 
  background: #979E71;
}
#menu ul li a { 
  font-weight: bold;
  padding: 15px 10px;
}
#menu li {
  position:relative; 
  float:left;
}
#menu ul li ul, #menu:hover ul li ul, #menu:hover ul li:hover ul li ul {
  display:none;
  list-style-type:none;
  width: 140px;
}
#menu:hover ul, #menu:hover ul li:hover ul, #menu:hover ul li:hover ul li:hover ul {
  display:block;
}
#menu:hover ul li:hover ul li:hover ul {
  position: absolute;
  margin-left: 145px;
  margin-top: -22px;
  font: 10px;
}
#menu:hover ul li:hover ul {
  position: absolute;
  margin-top: 1px;
  font: 10px;
}

<div id="menu">
  <ul>
    <li><center><a href="X">Home</a></center>
      <ul>
        <li><a href="#">About Us</a></li>
        <li><a href="#">Disclaimer</a></li>
      </ul>
    </li>	
    <li>
      <center><a href="#">Practice Areas</a></center>
      <ul>
        <li><a href="#">Civil Law</a></li>
        <li><a href="#">Criminal Law &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &rsaquo;</a>
          <ul>
            <li><a href="#">Joomla</a></li>
            <li><a href="#">Drupal</a></li>
            <li><a href="#">Wordpress</a></li>
          </ul>
        <li><a href="#">Family Law &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp;&nbsp; &rsaquo;</a>
          <ul>
            <li><a href="#">Joomla</a></li>
            <li><a href="#">Drupal</a></li>
            <li><a href="#">Wordpress</a></li>
          </ul>
        <li><a href="#">Personal Injury &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&rsaquo;</a>
          <ul>
            <li><a href="#">Joomla</a></li>
            <li><a href="#">Drupal</a></li>
            <li><a href="#">Wordpress</a></li>
          </ul>
        <li><a href="#">Traffic Offenses &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&rsaquo;</a>
          <ul>
            <li><a href="#">Joomla</a></li>
            <li><a href="#">Drupal</a></li>
            <li><a href="#">Wordpress</a></li>
          </ul>
        <li><a href="#">FAQ</a>	</li>
      </ul>
    </li>

    <li><center><a href="#">Attorney</a></center>
      <ul>
        <li><a href="#">X</a></li>
        <li><a href="#">X</a></li>
        <li><a href="#">X</a></li>
        <li><a href="#">X</a></li>
      </ul>
    </li>

    <li><center><a href="#">Contact Us</a></center>
      <ul>
        <li><a href="#">Locations &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&rsaquo;</a>
          <ul>
            <li><a href="#">Rockville Office</a></li>
            <li><a href="#">Frederick Office</a></li>
            <li><a href="#">Greenbelt Office</a></li>
          </ul>
        <li><a href="#">Phone Directory</a></li>
        <li><a href="#">Mailing Address</a></li>
      </ul>

    </li>

    <li><center><a href="#">Resources</a></center>
      <ul>
        <li><a href="#">Helpful Links</a></li>
        <li><a href="#">Affiliates &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&rsaquo;</a>
          <ul>
            <li><a href="#">Healthcare Providers</a></li>
            <li><a href="#">Insurance Companies</a></li>
          </ul>
        </li></ul>
    <li><center><a href="#">News &amp; Events</a></center>
      <ul>
        <li><a href="#">Press Articles</a></li>
        <li><a href="#">Newsletter</a></li>
        <li><a href="#">Events</a></li>
        <li><a href="#">Blog</a></li>
      </ul>
    <li><center><a href="#">Espanol</a></center>
      <ul>
        <li><a href="#">X</a></li>
      </ul>

  </ul>
</div>

Answer 1

将bottom:100%添加到您的#menu:hover ul li:hover ul规则

Demo 1

#menu:hover ul li:hover ul {
    position: absolute;
    margin-top: 1px;
    font: 10px;
    bottom: 100%; /* added this attribute */
}

---

或者更好的是，为了防止子菜单产生相同的效果，只需添加此规则

即可

Demo 2

#menu>ul>li:hover>ul { 
    bottom:100%;
}

---

Demo 3

来源：http://jsfiddle.net/W5FWW/4/

要返回边框，您可以添加以下属性

#menu>ul>li:hover>ul { 
    bottom:100%;
    border-bottom: 1px solid transparent
}

Answer 2

如果我们使用选择的下拉列表，则可以在css下面使用（不需要JS / JQuery）

{{1}}