我设置了以下媒体查询以针对各种 iOS 设备（iPad3、iPad2、iPhone4、iPhone3）。当我用 iPhone3 和 iPad2 加载此页面时，正确的 div 会被着色。但是，当我用 iPad3 加载此页面时，会加载 iPad2 和 iPhone4 样式，但不会加载 iPad3。（目前无法测试 iPhone4。）有什么想法吗？
<!DOCTYPE html>
<html>
<head>
<title></title>
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no;" />
<link rel="stylesheet" href="ipad3.css" media="only screen and (min-device-width:1536px) and (max-device-width:2048px) and (-webkit-min-device-pixel-ratio:2)" type="text/css" />
<link rel="stylesheet" href="ipad2.css" media="only screen and (min-device-width:768px) and (max-device-width:1024px) and (-webkit-min-device-pixel-ratio:0)" type="text/css" />
<link rel="stylesheet" href="iphone4.css" media="only screen and (min-device-width:640px) and (max-device-width:960px) and (-webkit-min-device-pixel-ratio:2)" type="text/css" />
<link rel="stylesheet" href="iphone3.css" media="only screen and (min-device-width:320px) and (max-device-width:480px) and (-webkit-min-device-pixel-ratio:0)" type="text/css" />
</head>
<body>
<div id="ipad3" style="width:200px;height:200px;border:1px solid black"></div>
<div id="ipad2" style="width:200px;height:200px;border:1px solid black"></div>
<div id="iphone4" style="width:200px;height:200px;border:1px solid black"></div>
<div id="iphone3" style="width:200px;height:200px;border:1px solid black"></div>
ipad3 should be RED
<br>
ipad2 should be GREEN
<br>
iphone4 should be BLUE
<br>
iphone3 should be ORANGE
</body>
</html>
..并且4个css文件被相应地编码（这个例子是iPad3.css文件）：
#ipad3 { background-color: red; }