Try this:
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<style>
._20 {
width: 16%;
display: inline;
float: left;
margin-left: 2%;
margin-right: 2%;
}
._30 {
width: 26%;
display: inline;
float: left;
margin-left: 2%;
margin-right: 2%;
}
label {
border: 1px solid #B3B3B3;
font-family: inherit;
padding: 3px;
width: 100%;
}
input {
border: 1px solid #B3B3B3;
font-family: inherit;
padding: 3px;
width: 100%;
}
.box {
padding: 10px;
margin: 10px 0px;
background-color: #666;
}
.content {
background-color: #FFFFFF;
padding: 10px;
-moz-border-radius: 6px;
overflow:hidden;
}
</style>
</head>
<body>
<div class="box">
<div class="content">
<div class="_20">
<p><label>Name:</label></p>
</div>
<div class="_30">
<p><input type="text" id="" /></p>
</div>
<div class="_20">
<p><label>Email:</label></p>
</div>
<div class="_30">
<p><input type="text" id="" /></p>
</div>
</div>
</div>
</body>
</html>
BTW, Check this out: How to create perfect form Markup and style it with CSS