白底黑字，纯文字显示。告别复杂，有简而生。
<!DOCTYPE html>
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>网站正在维护中</title>
<meta name="status" content="504" />
<meta http-equiv='X-UA-Compatible' content='IE=edge,chrome=1'>
<meta name="viewport" content="width=device-width, initial-scale=1">
<style type="text/css">
*{margin:0;padding:0;overflow:hidden;font-family:'Lato','Raleway','Courier New','Open Sans','sans-serif','Arial';letter-spacing:2px;}
body{text-align:center;color:#000;line-height:22px;font:15px/22px arial,sans-serif;text-transform:uppercase;0 1px 1px #060202font-weight:100;overflow:hidden;background-color:transparent;background-attachment:fixed;background-position:50% 0;background-repeat:no-repeat;background-size:cover;overflow:hidden;background:#f9f9f9;}
.overlay{position:absolute;top:0;left:0;width:100%;height:100%;opacity:0.6;background:rgba(255,255,255,0.51);z-index:10;}
#wrapper {position: absolute;z-index: 200;top: 50%;left: 50%; width: 100%;transform: translate(-50%, -50%);}
#content{padding:100% 0%;margin: 100% 0%;}
#content h1{font-weight:100;font-size:100px;line-height:120px;}
#content h2{font-size:18px;font-weight:200;}
a{color:#000;text-decoration:none;}a:hover{color:#1fb5ac;}
.cn{font-size:40px!important;}
</style>
</head>
<body>
<div class="overlay"></div>
<div id="wrapper">
<div id="content">
<h1 class="cn">网站正在维护中</h1>
<h2>请稍后......</h2>
</div>
</div>
</body>
</html>
