html - css 菜单子(monad)项未显示在正确的位置

Question

我将下面的代码用于 CSS 菜单，但子项未显示在父项下方

    #CustomerMenu ul {
  text-align: left;
  display: inline;
  margin: 0;
  padding: 15px 4px 17px 0;
  list-style: none;
  -webkit-box-shadow: 0 0 5px rgba(0, 0, 0, 0.15);
  -moz-box-shadow: 0 0 5px rgba(0, 0, 0, 0.15);
  box-shadow: 0 0 5px rgba(0, 0, 0, 0.15);
}
#CustomerMenu ul li {
    display: inline-block;
}
#CustomerMenu ul li a {
  font: bold 12px/18px sans-serif;
  margin-right: -4px;
  position: relative;
  padding: 15px 20px;
  background: #fff;
  cursor: pointer;
  -webkit-transition: all 0.2s;
  -moz-transition: all 0.2s;
  -ms-transition: all 0.2s;
  -o-transition: all 0.2s;
  transition: all 0.2s;
}
#CustomerMenu ul li a:hover {
  background: #555;
  color: #fff;
}
#CustomerMenu ul li ul {
  padding: 0;
  position: absolute;
  top: 48px;
  left: 0;
  width: 150px;
  -webkit-box-shadow: none;
  -moz-box-shadow: none;
  box-shadow: none;
  display: none;
  opacity: 0;
  visibility: hidden;
  -webkit-transiton: opacity 0.2s;
  -moz-transition: opacity 0.2s;
  -ms-transition: opacity 0.2s;
  -o-transition: opacity 0.2s;
  -transition: opacity 0.2s;
}
#CustomerMenu ul li ul li a { 
  background: #555; 
  display: block; 
  color: #fff;
  text-shadow: 0 -1px 0 #000;
}
#CustomerMenu ul li ul li a:hover {
    background: #666;
}
#CustomerMenu ul li:hover ul {
  display: block;
  opacity: 1;
  visibility: visible;
}

如何让子项显示在父项的正下方。

我在这里创建了一个 JS Fiddle 来展示我目前拥有的完整示例

http://jsfiddle.net/h4joet22/

Answer 1

演示 - http://jsfiddle.net/h4joet22/1/

设置li的position:relative

#CustomerMenu ul li {
    display: inline-block;
    position:Relative;
}

编辑

设置 li 激活

演示 - http://jsfiddle.net/h4joet22/2/