[Java script] head visual width
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<style>
.w100{width:100%}
.w1200{width:1200px; margin:0 auto;}
body{
background: #eee;
}
#header_wrap {
background: #fff;
height:100px;
}
#visual {
height: 500px;
margin-top: 30px;
background: red;
}
</style>
<body>
<div id="wrap" class="w100">
<div id="header_wrap" class="w100">
<div id="header" class="w1200">
</div>
</div>
<div id="visual_wrap" class="w100">
<div id="visual" class="w1200">
visual
</div>
</div>
</div>
</body>
</html>