Aligning a ul to the middle for horizontal CSS menus

I am trying to have a horizontal menu, but the ul is aligned to the right instead of in the middle.

Here are my CSS and HTML:

CSS:

#menu
{
    clear: both;
    float: left;
    width: 830px;
    display: inline;
    position: relative;
    z-index: 1;
    border-top: 1px solid #e9e6d9;
    border-bottom: 1px solid #e9e6d9; 
    margin: 0 auto;
    background-color:#FFFFFF;
    padding: 0;
}
#menu ul {
    margin: 0;
    display: block;
    text-align: center;
    padding: 0;
    float: right;
}
#menu li {
    /*font-family: Georgia, "Times New Roman", Times, serif;*/
    font-family: sans-serif, Helvetica, Arial;
    font-size: 13px;
    font-weight: normal;
    float: left;
    position: relative;
    list-style: none;
    margin: 0;
    display: inline-block;
    padding: 0;
}

HTML:

<div id="menu">
    <ul>
        <li>
            <a href="http://www.tahara.es/">
                <span>HOME</span>
            </a>
        </li>
        <li>
            <a href="http://www.tahara.es/shop/">
                <span>SHOP</span>
            </a>
        </li>
    </ul>   
</div>

Thanks in advance for any suggestion!

Solution

You can remove your float properties. Just add a width to your #menu ul and add margin : 0 auto; to make it centered.

Example :

#menu ul {
    width: 300px;
    margin: 0 auto;
}

Live demo here : http://codepen.io/joe/pen/uAaHo