Your CSS syntax is messed up. First of all, you either need to have your CSS code in a <style> tag or you need to have it in a separate .css file and load it through a <link> tag. Second, you can't just have "div1". You either need to make it a class or an ID. Like so.
/* This is an ID */
#div1 {
}
/* This is a class */
.div1 {
}
IDs
Each element can have only one ID
Each page can have only one element with that ID
Classes
You can use the same class on multiple elements.
You can use multiple classes on the same element.
Moving on, you didn't follow my CSS code. First of all, lets point out your image tags, the only time you need to define the "width" and "height" attributes are when you're resizing the image. You don't need to define the default width and height. Second, lets point out on how you plan on doing this. What it looks like to me is you're trying to create a basic layout like so.
TOP OF PAGE
CONTENT
BOTTOM OF PAGE
Which is fine, but you should try and do it differently. What I'd recommend is creating 4 IDs. A main wrapper, a header, a content, and a footer. Something like this would work just fine.
<style>
#wrapper {
width: 920px;
margin-left: auto;
margin-right: auto;
}
#header {
/* Define styles here */
}
#content {
/* Define styles here */
}
#footer {
/* Define styles here */
}
</style>
<div id="wrapper">
<div id="header">
<img src="topborder.png" />
</div>
</div>
That code is tested and the topborder should be centered. If you need help with CSS and HTML,
http://www.w3schools.com/css/default.asp w3schools is an amazing site for just that.