html>
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
<body background="E:/aa/a.jpg" style="background-repeat:no-repeat ;background-size:100% 100%;
background-attachment: fixed;" >
<div id="box">
<div id="title" align="center">
<br><br><br><br><br><br><br>
<font face="微软雅黑" size="10">
welcome!
</font>
</div>
<hr width="380px" size="2" align="center">
<div id="text">
<font face="微软雅黑" size="4">
<center><u>It's my first website!</u></center>
</font>
</div>
</div>
<nav>
<center>
<ul type="none">
<li>奇奇怪怪的功能</li>
<li><a href="https://www.csdn.net/">进入 CSDN</a></li>
<li><a href="html.html">意见箱</a></li>
</ul>
</center>
</nav>
</body>
</body>
</html>
求大佬帮忙看一下
完全不知道要怎么弄