SOURCE

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  var ime=document.getElementById('ime');
  var clo=document.getElementById('close');
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<div id='outer'>
	<button>输入法</button>
	<ul id='ime'>
		<li><a href='#'>手写</a></li>
		<li><a href='#'>拼音</a></li>
		<li id='close'><a href='#'>关闭</a></li>
	</ul>
</div>

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body{font:12px/1.5 Tahoma;}
ul{list-style-type:none;}
button{cursor:pointer;}
#outer{width:70px;margin:10px auto;}
#ime{margin-top:5px;background:#fff;border:1px solid #9a99ff;display:none;}
#ime li{width:100%;line-height:24px;display:inline-block;vertical-align:top;}
#close{border-top:1px solid #9a99ff;}
#ime li a{color:#00c;padding:0 5px;display:block;text-decoration:none;}
#ime li a:hover{background:#d9e1f6;}