Divs centreing in Firefox/Chrome but not IE

[Chris Cordner]

Good Evening

I am building a website using DIVs and CSS.

I have everything in a container DIV, which I want to centre on the page. The CSS is below:

#container{ 
    width: 100%;
    max-width: 1000px;
    width:expression(document.body.clientWidth > 1000? "1000px": "auto" );
    float: center;
    color: #fff;    
    margin-left: auto;
    margin-right: auto;
    padding: 0px;
    border-width: 0px
        } 

Yet for some reason, in IE it won't center. Any idea why?

On a similar vein, within the container I have a navigation bar. For some reason, it just won't center. I thought it was because it was a <ul> and then indented, but I have tried setting margin and padding to zero.

Any ideas?

Code below:

#navbar ul {
    margin-left: 0px;
    margin-right: 0px;
    padding-left: 0px;
    padding-right: 0px;
    height: 27px;
    list-style-type: none;
    text-align: center;
    font-weight: bold;
    font-size: 13px;
    border-width: 0px
        } 
 
#navbar ul li {  
    display: inline;
    height: 25px;
    width: 100px;
    text-align: center;
    border-width: 0px
        } 
 
#navbar ul li a { 
    float: left;
    width: 100px;
    margin-left: 10px;
    margin-right: 10px;
    text-decoration: none;
    display: inline;   
    line-height: 25px;
    color: #fff; 
    border-width: 0px;
    background: url("buttons.jpg") no-repeat 0 0
        } 

Thanks
Chris

[drhowarddrfine]

In the first, there is no such thing as 'float:center'. Also, Microsoft dropped support for 'expression' in IE8.