CSS - List tree background issue

I have a list with multiple sections. I try to make it look like a kind of tree. It started quite well but I can't fix the last bits.

The code can be found at:

http://jsfiddle.net/Kwfpm/

Here is how it should work

• The first "Datorer", "Mjukvara" and "Microsoft" should be connected to the tree with a horisontal line.
• "Mjukvara" at the bottom left should be connected to "Kategorier".

There are some repeated problems but these should be solved if the two above is solved.

Here is a link what it should look like (without the collapsing things):

Open and close to see the tree: http://jquery.bassistance.de/treeview/demo/prerendered.html

Info

• I don't know how many levels there are.
• The HTML can't be changed because its generated by Wordpress
• Use backgrounds or borders to show what you got.

If JSfiddle don't work you can use this:

CSS

    * {
    margin: 0;
    padding: 0;
}
.sidebar > ul > li {
    background: none;
}
li {
    padding-left: 20px;
    list-style: none;
    background: url('http://www.jenst.se/images/normal.png') repeat-y 10px 0;
    color: #333;
    font-family: Arial;
    font-size: 13px;
    line-height: 22px;
}
li a {
    color: #555;
}
li:last-child {
    background: url('http://www.jenst.se/images/lastchild.png') no-repeat 10px 0px;
}

HTML

<div class="sidebar default">
<ul>
    <li id="categories-10" class="widget widget_categories">
        <h4 class="title">Kategorier</h4>
        <ul> 
            <li class="cat-item cat-item-7"><a href="http://localhost/concepts/addmod/category/sjukt-lang-kategori-som-tar-for-mycket-plats/" title="Se alla inlägg sparade under Datorer">Datorer</a> 
            </li> 
            <li class="cat-item cat-item-3"><a href="http://localhost/concepts/addmod/category/testkategori/" title="Se alla inlägg sparade under Mjukvara">Mjukvara</a> 
                <ul class='children'> 
                    <li class="cat-item cat-item-4"><a href="http://localhost/concepts/addmod/category/testkategori/underkategori/" title="Se alla inlägg sparade under Hårdvara">Hårdvara</a> 
                        <ul class='children'> 
                            <li class="cat-item cat-item-6"><a href="http://localhost/concepts/addmod/category/testkategori/underkategori/underkategori-2/" title="Se alla inlägg sparade under Microsoft">Microsoft</a>
                            </li> 
                            <li class="cat-item cat-item-9"><a href="http://localhost/concepts/addmod/category/testkategori/underkategori/bla/" title="Se alla inlägg sparade under Office-paket">Office-paket</a> 
                            </li> 
                        </ul> 
                    </li> 
                </ul>
            </li>
            <li class="cat-item cat-item-3"><a href="http://localhost/concepts/addmod/category/testkategori/" title="Se alla inlägg sparade under Mjukvara">Mjukvara</a> 
                <ul class='children'> 
                    <li class="cat-item cat-item-4"><a href="http://localhost/concepts/addmod/category/testkategori/underkategori/" title="Se alla inlägg sparade under Hårdvara">Hårdvara</a> 
                        <ul class='children'> 
                            <li class="cat-item cat-item-6"><a href="http://localhost/concepts/addmod/category/testkategori/underkategori/underkategori-2/" title="Se alla inlägg sparade under Microsoft">Microsoft</a>
                            </li> 
                            <li class="cat-item cat-item-9"><a href="http://localhost/concepts/addmod/category/testkategori/underkategori/bla/" title="Se alla inlägg sparade under Office-paket">Office-paket</a> 
                            </li> 
                        </ul> 
                    </li> 
                </ul>
            </li>
        </ul> 
    </li>
    <li id="categories-10" class="widget widget_categories">
        <ul> 
            <li class="cat-item cat-item-7"><a href="http://localhost/concepts/addmod/category/sjukt-lang-kategori-som-tar-for-mycket-plats/" title="Se alla inlägg sparade under Datorer">Datorer</a> 
            </li> 
            <li class="cat-item cat-item-3"><a href="http://localhost/concepts/addmod/category/testkategori/" title="Se alla inlägg sparade under Mjukvara">Mjukvara</a> 
                <ul class='children'> 
                    <li class="cat-item cat-item-4"><a href="http://localhost/concepts/addmod/category/testkategori/underkategori/" title="Se alla inlägg sparade under Hårdvara">Hårdvara</a> 
                        <ul class='children'> 
                            <li class="cat-item cat-item-6"><a href="http://localhost/concepts/addmod/category/testkategori/underkategori/underkategori-2/" title="Se alla inlägg sparade under Microsoft">Microsoft</a>
                            </li> 
                            <li class="cat-item cat-item-9"><a href="http://localhost/concepts/addmod/category/testkategori/underkategori/bla/" title="Se alla inlägg sparade under Office-pa开发者_C百科ket">Office-paket</a> 
                            </li> 
                        </ul> 
                    </li> 
                </ul>
            </li>
        </ul> 
    </li>
</ul>
</div>

Have a look at this javascript treeview: http://krijnhoetmer.nl/stuff/javascript/list-treeview-menu/

It does have a same structure as you prefer with li's and ul's. Maybe you could take a look at it with firebug.

I figured it out. Here is a working code:

http://jsfiddle.net/Kwfpm/3/

The red borders can be changed to a background image horizontal lines.