Avevo creato un menu' formato da varie div che ho specificato nel foglio CSS, ma quelle div usando "float: left" appaiono nella div successiva e non sopra :S Questi sono i codici:

HMTL:

codice:
<html>
<head>
<title>Ristorante Cafè Mar - Pizzeria</title>
<link href="css.css" rel="stylesheet" type="text/css">
</head>
<body>
<div class="banner"></div>

<div class="sinistra"></div>
<div class="home"></div>
<div class="foto"></div>
<div class="dovesiamo"></div>
<div class="contattaci"></div>
<div class="destra"></div>


<div class="top"></div>
<div class="center">
<center>
TESTO
</center></div>
<div class="bottom">





Copyright 20<? echo (date("y")); ?> &copy . All rights reserved.
</body>
</html>
CSS:

codice:
body {
background-image: url(img/bg.png);
}

.banner{
background-image: url(img/banner.png);
height: 108px;
width: 896px;
margin-bottom: 30px;
margin-left: auto;
}

.sinistra{
background-image: url(img/sinistra.png);
height: 31px;
width: 12px;
margin-left: 100px;
float: left;
}

.destra{
background-image: url(img/destra.png);
height: 31px;
width: 12px;
float: left;
}

.home{
background-image: url(img/home.png);
height: 31px;
width: 159px;
float: left;
}

.home:hover{
background-image: url(img/homehover.png);
height: 31px;
width: 159px;
}

.foto{
background-image: url(img/foto.png);
height: 31px;
width: 159px;
float: left;
}

.foto:hover{
background-image: url(img/fotohover.png);
height: 31px;
width: 159px;
}

.dovesiamo{
background-image: url(img/dovesiamo.png);
height: 31px;
width: 159px;
float: left;
}

.dovesiamo:hover{
background-image: url(img/dovesiamohover.png);
height: 31px;
width: 159px;
}

.contattaci{
background-image: url(img/contattaci.png);
height: 31px;
width: 159px;
float: left;
}

.contattaci:hover{
background-image: url(img/contattacihover.png);
height: 31px;
width: 159px;
}

.top{
background-image: url(img/top.png);
height: 18px;
width: 899px;
}

.center{
background-image: url(img/center.png);
height: auto;
width: 899px;
}

.bottom{
background-image: url(img/bottom.png);
height: 18px;
width: 899px;
}