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<div class="background">

body
{
	background-image:url('http://pic.90sjimg.com/back_pic/qk/back_origin_pic/00/02/29/804033ff5e3a1d42abd9a7d62f59e222.jpg');
	background-repeat:no-repeat;
	background-position:left top;
	margin-right:200px;
}

ul
{
	list-style-type:none;
	margin:0;
	padding:0;
	overflow:hidden;
  
  
}
li
{
	float:left;
}
a:link,a:visited
{
	display:block;
	width:200px；
  font-weight:bold;
	color:#FFFFFF;
	background-color:0000ff;
	text-align:center;
	padding:4px;
	text-decoration:none;
  text-transform:uppercase;
   opacity:0.5;
	
}
a:hover,a:active
{
	background-color:#dbdbf8;
}