css help pls

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<style>
html,body{
 margin:0;
 padding:0;
 height:100%;
 width: 100%;
}

.container{
width: 200px;
height: 50px;
border: 1px solid red;
overflow: auto;
}

.kids{
float: left;
border: 1px solid blue;
width: 20px;
height: 45px;
}
</style>
</head>
<body>
<div class="container">
 <div class="kids">{123}</div>
 <div class="kids">{123}</div>
 <div class="kids">{123}</div>
 <div class="kids">{123}</div>
 <div class="kids">{123}</div>
 <div class="kids">{123}</div>
 <div class="kids">{123}</div>
 <div class="kids">{123}</div>
 <div class="kids">{123}</div>
 <div class="kids">{123}</div>
</div>
</body>
</html>