los div tiene color de fondo...no deberia ocurrir eso, aca va el codigo html y css
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Noticias</title>
<meta http-equiv="content-type" content="text/html; charset=utf-8" />
<link href="estilos/estilo2.css" rel="stylesheet" type="text/css" media="screen"/>
</head>
<body>
<div id="wrapper">
<div id="header">
<h1 id="logo"><a href="/" title="Homepage">hola</a></h1>
</div>
<div id="leftcolumn">
<div id="menu">
<ul class="menu">
<li><a href="#">Home</a></li>
<li><a href="#">Nosotros</a></li>
<li><a href="#">Horarios</a></li>
<li><a href="#">Contacto</a></li>
</ul>
</div>
</div>
<div id="content">
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer nec odio. Praesent libero. Sed cursus ante dapibus diam. Sed nisi. Nulla quis sem at nibh elementum imperdiet. Duis sagittis ipsum. Praesent mauris. Fusce nec tellus sed augue semper porta. Mauris massa. Vestibulum lacinia arcu eget nulla.</p>
</div>
<div id="rightcolumn">
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer nec odio. Praesent libero. Sed cursus ante dapibus diam. Sed nisi. Nulla quis sem at nibh elementum imperdiet. Duis sagittis ipsum. Praesent mauris. Fusce nec tellus sed augue semper porta. Mauris massa. Vestibulum lacinia arcu eget nulla.</p>
</div>
<div id="footer">
<p>This is the Footer</p>
</div>
</div>
</body>
</html>
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@import url("reset.css");
body{ background-color:#607462;}
p {
padding: 10px;
}
#wrapper {
margin: 0 auto;
width: 960px;
}
#header {
height: 175px;
width: 960px;
background-image:url(../imagenes/header.png);
}
h1{
background-image:url(../imagenes/logo.png);
background-repeat:no-repeat;
width:232px;
height:73px;
text-indent:-9999px;
position:absolute;
top:23px;
margin-left:18px;
}
ul {
display: block;
}
ul li a{
text-decoration:none;
color: #3c5247;
font-size:1em;
font-family:"Arial", Verdana, sans-serif;
line-height:22px;
margin-left:20px;
}
#content {
float: left;
background: #FFFFFF;
width: 720px;
}
#leftcolumn {
background: #bec7bf;
width: 120px;
height:115px;
float: left;
border-radius: 0 0 10px 10px;
margin-top:-46px;
padding-top:10px;
}
#rightcolumn {
background: #CC33FF;
width: 120px;
float: left;
}
#footer {
height: 62px;
width: 960px;
background: #33FF66;
clear: both;
}