1、html布局源码：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=Edge,chrome=1">
<meta name="viewport"
content="width=device-width, initial-scale=1, maximum-scale=1, minimum-scale=1, user-scalable=no">
<title>石柱</title>
<!--<link rel="shortcut icon" href="images/wn-icon.ico" type="image/x-icon">-->
<link rel="stylesheet" href="js/js/zTree_v3/css/zTreeStyle/zTreeStyle.css" type="text/css">
<link href="./Build/Cesium/Widgets/widgets.css" rel="stylesheet">
<link href="./css/font-awesome.min.css" rel="stylesheet">
<!--<link href="./css/pretty.css" rel="stylesheet">-->
<link rel="stylesheet" href="AMstyle/stylesheets/bootstrap.css" type="text/css">
<link rel="stylesheet" href="AMstyle/am.css" type="text/css">
<link rel="stylesheet" href="AMstyle/gtfont.css" type="text/css">
<script type="text/javascript" src="js/AMjs/jquery.min.js"></script>
<script type="text/javascript" src="js/js/zTree_v3/js/jquery.ztree.core.js"></script>
<script type="text/javascript" src="js/js/zTree_v3/js/jquery.ztree.excheck.js"></script>
<script type="text/javascript" src="js/AMjs/bootstrap.js"></script>
<!--图表-->
<script type="text/javascript" src="js/AMjs/highcharts.js"></script>
<script type="text/javascript" src="js/AMjs/vue.js"></script>
<script type="text/javascript" src="js/AMjs/vue-resource.js"></script>
<script type="text/javascript" src="js/AMjs/vue-router.min.js"></script>
<!--IE兼容-->
<script type="text/javascript" src="js/AMjs/respond.js"></script>
<!--supermap环境-->
<script src="js/slider.js"></script>
<script src="js/config.js"></script>
<script type="text/javascript" src="js/AMjs/require.min.js" data-main="js/AMjs/main"></script>
<script type="text/javascript" src="js/AMjs/main/initSuperMap_scene.js"></script>
<script type="text/javascript" src="js/AMjs/am.js"></script>
以下的样式部分尤为重要，如果没有这些样式，就无法实现在不同的浏览器窗口及不同的分辨率下实现始终都垂直水平居中
<style>
body {
100%;
height: 100%;
margin: 0;
padding-top: 76px;
padding-left: 14px;
padding-right: 14px;
padding-bottom: 14px;
overflow: visible;
background-color: #1a262e;
}
html, #cesiumContainer {
100%;
height: 100%;
margin: 0;
padding: 0;
overflow: hidden;
background-color: #ffffff;
}
#cesiumContainer .cesium-viewer-bottom {
display: none;
}
.measureCur {
cursor: url(./images/cur/measure.cur), auto;
}
.drawCur {
cursor: url(./images/cur/draw.cur), auto;
}
.positionAdjust {
150px;
margin: 0;
margin-left: 55px;
display: inline-block;
top: -45px;
position: relative;
}
.bubble {
text-align: center;
position: absolute;
padding: 15px 30px;
margin: 0;
color: #fff;
background: #5a8f00;
background: -webkit-gradient(linear, 0 0, 0 100%, from(#b8db29), to(#5a8f00));
background: -moz-linear-gradient(#b8db29, #5a8f00);
background: -o-linear-gradient(#b8db29, #5a8f00);
background: linear-gradient(rgba(7, 86, 152, 0.3), rgba(46, 136, 196, 0.3));
-webkit-border-radius: 10px;
-moz-border-radius: 10px;
border-radius: 10px;
max- 330px;
max-height: 450px;
}
.bubble:after {
content: "";
position: absolute;
bottom: -50px;
left: 50px;
border- 0 20px 50px 0px;
border-style: solid;
border-color: transparent rgba(46, 136, 196, 0.3);
display: block;
0;
}
</style>
</head>
<body class="login-bg">
<div class="container container1">
<div class="modal-dialog width-400 modal-dialog1" role="document">
<div class="modal-content bg3">
<div class="modal-header text-center modal-header1">
<h2 class="modal-title">XXX管理系统</h2>
</div>
<div class="modal-body modal-body1">
<div class="panel panel-default panel1">
<div class="panel-heading panel-heading2">
<h4><span class="log-in">用户登录</span></h4>
</div>
<div class="panel-body panel-body1">
<form class="form-horizontal">
<div class="form-group">
<label for="login" class="col-sm-3 control-label2">
<i class="icon-user"></i>用 户</label>
<div class="col-sm-9">
<input type="text" class="form-control" name="username" id="username"
placeholder="Username" onblur="if(placeholder==''){placeholder='Username'}"
onfocus="if(placeholder=='Username'){placeholder=''}"
style="color: #2c3a45">
</div>
</div>
<div class="form-group">
<label for="password" class="col-sm-3 control-label2"><i class="icon-lock"></i>
密 码</label>
<div class="col-sm-9">
<input type="password" class="form-control" name="password" id="password"
placeholder="Password" onblur="if(placeholder==''){placeholder='Password'}"
onfocus="if(placeholder=='Password'){placeholder=''}"
style="color: #2c3a45">
</div>
</div>
<div class="form-group">
<input type="button" id="reset" class="reset" value="重置"/>
<input type="button" id="login" class="login" value="登陆"/>
</div>
</form>
</div>
</div>
</div>
<div class="Error_prompt">
<span>该用户不存在或密码错误，请更换账户!</span>
</div>
</div>
</div>
</div>
<script>
$(function () {
$(".Error_prompt").hide();
$("#login").on("click", function () {
if ($("#username").val() == "" || $("#password").val() == "") {
$(".Error_prompt").fadeIn(800).html("用户名或密码不能为空！");
return false;
}
if ($("#username").val().length < 6) {
$(".Error_prompt").fadeIn(800).html("您的用户名小于6位！");
return false;
}
if ($("#password").val().length < 6) {
$(".Error_prompt").fadeIn(800).html("您的密码小于6位！");
return false;
}
else {
$(".Error_prompt").fadeOut(400);
}
})
});
</script>
</body>
</html>
2、css样式：关键步骤
2.1、背景图片铺满整个浏览器
.login-bg{
background-size: cover;
background-repeat: no-repeat;
background-attachment:fixed; 这一条必须有，否则可能没有效果
}
2.2、整个窗口始终水平垂直居中显示，在不同的分辨率及浏览器窗口大小窗口下都是一致的
第二层：
.modal-dialog {
display: table-cell;
vertical-align: middle;
}
最外层：
.container {
display: table;
height: 100%;
}
注：使用固定定位或者绝对定位是不可能真正的实现居中显示的，只是实现了在当前分辨率及当前浏览器窗口下实现了，不是永久之计。也不能使用margin及padding来实现，默认的是模态框距离顶部是30px的距离，改了也是治标不治本。还有一种说法是使用js修改使之获取到登陆框到窗口上下左右各个方面的距离，从而使之相等，杀鸡焉用牛刀。能用css解决的不用那么费力，