Sprites not displaying

Question

Sprite rollover images not displaying.

The goal is to have a row of icons with a rollover controlled by CSS.

Currently, the code below does not display any images...what am I missing?

CSS:

    #social {
    margin: 0; 
    padding: 0; 
    height: 15px;
}
#social li {
    margin: 0 5px 0 0; 
    padding: 0; 
    list-style-type: none; 
    display: inline; 
    height: 15px;
    float: left;
}
#social li.last{
    margin-right:0px;
}
#social li a {
    background-image: url("../images/icon_twitter.png") 0px 0px; 
    background-repeat: no-repeat;
    display: block;
    height: 15px;
    width: 18px;
}
#social li#social-twitter a{
    background-position: 0px 0px;
}
#social li#social-twitter a:hover {
    background-position: 0px -15px;
}
#social li#social-youtube a{
    background-position: -18 top;
}
#social li#social-youtube a:hover {
    background-position: -18 -15px;
}
#social span {
    display: none;
}

HTML:

<ul id="social">
<li id="social-twitter"><a href="#"><span>Twitter</span></a></li>
<li id="social-youtube" class="last"><a href="#"><span>Youtube</span></a></li>
</ul> 

Answer 1

You are trying to set the background position within background-image.

Change this:

background-image: url("../images/icon_twitter.png") 0px 0px; 

To this:

background-image: url("../images/icon_twitter.png"); 
background-position: 0px 0px;