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                        /形形色色的下拉菜单

为什么我背景图片显示不了，求解啊

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>多级下拉菜单</title>
    <style type="text/css">

        #navmenu{
           list-style: none;  
        }
        #navmenu li{
            float: left;
            height: 40px;
            position: relative;
            padding: 0; 
        }
        #navmenu li a{
            margin-top: 1px;
            text-decoration: none;
            padding: 0 10px;
            text-align: center;
            display: block;
            height: 40px;
            line-height: 40px;
            background-color: #111111;
            color:#ffffff;
            border-right: 2px solid #fff;
        }
        #navmenu li ul{
            list-style: none;
            display: none;
            position: absolute;
            top: 40px;
            left: -40px;
        }
        #navmenu li ul li{
            width: 94px;
            margin-top: 1px;
        }
        #navmenu li a:hover{
            background:url(C:\Users\Administrator\Downloads\Sublime Text Build 3083\jQuery\形形色色的下拉菜单\4\03\7270087_170855295352_2.jpg) 0 0 repeat-x;
            color: #fff;
        }
        #navmenu li:hover ul{
            display: block;
        }

    </style>
</head>
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