Css playing up

programming web dev
1

http://www.brendanmeade.co.nz/site/index.php

Hi for some reason
these div areas wont listen to the css in IE and also in safari??

any gurus know whats up?

</head>

<body>
<div id="mainArea">
<div id="contentArea"><div id="sidebar"></div></div>
<div class="bulkcontent">dssasasdasdsd</div>
<div id="footer"></div>
</div>

</body>

</head>
</html>

This is the css




div#contentArea {
  width: 800px;
  float: left;
  background: url(/images/headernew.jpg) top right no-repeat;
  height: 158px;
   border: 2px solid #fff;
      margin-top: 2px;

}
div#mainArea {
  width: 800px;
  background: #444233;
 
    margin: 50px;
}
div#footer {
	background: url(/images/footer.png) bottom no-repeat;
	width: 800px;
	height: 30px;
	border: 2px solid #fff;
	position: bottom;
	}
	
div#sidebar{
width: 200px;
height: 158px;
background: #0FAFC1;
position: left top;
 border: 2px solid #fff;
}

div.bulkcontent{
width: 800px;
height: 350px;
background: #fff;
}