Question: I've got a list with list-style-none which needs to be able to add new items to itself via Ajax and have the background expand appropriately when it does. Adding via Ajax is easy, but every solution I try for the background fails me. I don't know if it's even possible; is it? I'm using a grid like this one:

<http://jqueryui.com/demos/sortable/#display-grid>

Both WebKit and Firebug are showing me skinny, empty bars when I hover over the enclosing divs and/or the enclosing ul tag. It appears that the minute you set a list loose with list-style-none and float:wherever, you give up control over its background. But that can't be right.

Answer: 
Could you provide a sample of your code? Also, why does the list have display:none set?

For instance, should be as simple as this:

HTML:

```
<ul id="dest"></ul>

```

JS:

```
// Simplified example, most likely wrapped in $.ajax
// This is the AJAX response function  
function(data, response) {
    var items = json.parse(data);
    $.each(items, function() {
         // Assumes item has a name property
         $('#dest').append($('<li>' + this.name + '</li>'));     
    });
}

```

Should be just that simple. You shouldn't need the hide the list initially, as you can simply append list items and have the display update appropriately.

Hope that helps.
For dealing with the float element, maybe you should know it's characteristic, gotcha, and how to deal with it.
See the links below, it also have demo, so you can understand the concept:

1. <http://www.smashingmagazine.com/2009/10/19/the-mystery-of-css-float-property/>
2. <http://www.smashingmagazine.com/2007/05/01/css-float-theory-things-you-should-know/>
3. <http://aloestudios.com/2009/12/goodbye-overflow-clearing-hack/>
and
<http://aloestudios.com/misc/overflow/>