My site displays fine in my google chrome, but not in IE or Firefox.

Thank you for any help!

Here is the code

HTML:
Code:
<!DOCTYPE html>
<html>
  <head>
    <title>Bob's Budget Batteries</title>
    <link rel="stylesheet" type="text/css" href="/960fw/css/960_12_col.css" />
    <link rel="stylesheet" type="text/ces" href="/css/home.css" />
 </head>
  <body>
    <div class="container_12 clearfix">
      <div id="header" class="grid_2">
	<img  src="img/boblogo.svg" alt="Bob's Budget Batteries" width ="120" height="120"/>
        <div id="nav" class="grid_12">
	 <a href="">Services</a>
         <a href="">Products</a>
	 <a href="">About Us</a>
	 <a href="">Contact Us</a>
      </div>
     </div> 
    </div>
  </body>
</html>






CSS:
Code:
* {
    font-family: Arial, Verdana, sans-serif;
    color: #665544;
    text-align: center;
  }
#nav {
    background-color: #33CC33;
    margin-top: 20px;
    padding: 15px 0px 15px 0px;
      }
a {
    padding: 10px;
    margin-left: 15 px;
    margin-right: 15px;
   }