html - Semantic-Ui Dropdown调整宽度和对齐中心

Question

我无法调整下拉框的宽度和居中对齐这是代码:my code on fiddle to check我使用语义 UI 流体下拉菜单

<div id="123">
<div class="ui fluid selection dropdown ">
<input id="dpdown" type="hidden" name="user">
<i class="dropdown icon"></i>
<div class="default text">Select Friend</div>
<div class="menu">
<div class="item" data-value="jenny">
  <img class="ui mini avatar image" src="/images/avatar/small/jenny.jpg"> 
 Jenny Hess
</div>
<div class="item" data-value="elliot">
  <img class="ui mini avatar image" src="/images/avatar/small/elliot.jpg"> 
Elliot Fu
</div>
<div class="item" data-value="stevie">
  <img class="ui mini avatar image" src="/images/avatar/small/stevie.jpg"> 
Stevie Feliciano
</div>
<div class="item" data-value="christian">
  <img class="ui mini avatar image" 
src="/images/avatar/small/christian.jpg"> Christian
</div>
<div class="item" data-value="matt">
  <img class="ui mini avatar image" src="/images/avatar/small/matt.jpg"> 
Matt
</div>
<div class="item" data-value="justen">
  <img class="ui mini avatar image" src="/images/avatar/small/justen.jpg"> 
Justen Kitsune
</div>
</div>
</div>

Answer 1

ID 不能以数字开头，并且是 width: 50px;。

#container {
  width: 200px;
  margin: 0 auto;
}

http://jsfiddle.net/gzstes0z/