Bootstrap dropdowns menus appearing behind other elements - IE7

Question

I'm using Bootstrap 2.3.1 http://twitter.github.io/bootstrap/index.html

So I'm using their 'dropdown-menu' class to create some simple quick use dropdown menus, but for some reason on IE7 they are appearing behind text and other elements on my site.

Test Link: http://leongaban.com/_projects/defakto/CDS/

I added z-index to my CSS, but still doesn't seem to do anything, please help!

.header .header-nav ul#nav-account ul.dropdown-menu,
.header .header-nav ul#nav-library ul.dropdown-menu {
    z-index: 10000;
}

IE9, Chrome, FF and other modern no headache browsers:

---

IE7 >:(

HTML

<div class="header-nav">

<ul id="nav-account" role="navigation" class="pull-right">

    <!-- Language Dropdown Button -->
    <li id="language-btn">
        <a href="#" id="drop1" class="dropdown-toggle" data-toggle="dropdown">English</a>
        <img src="img/header-small-down-arrow.png" alt="grey triangle"/><!-- <span class="grey_triangle"></span>-->

        <!-- Language Dropdown Menu-->
        <ul class="dropdown-menu" role="menu" aria-labelledby="drop1">
            <li role="presentation"><a role="menuitem" tabindex="-1" href="#">English</a></li>
            <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Spanish</a></li>
            <li role="presentation"><a role="menuitem" tabindex="-1" href="#">German</a></li>
            <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Japanese</a></li>
            <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Chinese</a></li>
        </ul>
    </li>

    <!-- User Dropdown Button -->
    <li id="account-btn">
        <a href="#" id="drop2" class="dropdown-toggle" data-toggle="dropdown">Logout</a>
        <img src="img/header-small-down-arrow.png" alt="grey triangle"/>
        <!-- <span class="grey_triangle"></span> -->

        <!-- User Dropdown Menu-->
        <ul class="dropdown-menu" role="menu" aria-labelledby="drop2">
            <li role="presentation"><a role="menuitem" tabindex="-1" href="http://google.com">Logout</a></li>
            <li role="presentation"><a role="menuitem" tabindex="-1" href="#anotherAction">Account</a></li>
        </ul>
    </li>
</ul>

Answer 1

Its a stacking context issue!

Even though you are using z-index on the dropdown, it is only relative to elements in the same stacking context. You need to add a z-index and a position to a parent element in order to get this to work. In this case I would recommend the header-top div