Google maps z-index

I am using v2 of the api, and on rollover of the top navigation, the drop downs are under the map. I tried givin开发者_运维百科g the map div container position relative with a lower z-index. and raising the nav z-index and can't get it to work

Any ideas? Please select NY for the most results. demo link

UPDATE by traveling up the hierarchy I was able to z-index properly.

    #main-content {
background: url(../img/bg/bg-main-cont.png) no-repeat top left;
width: 920px;
margin: -4px auto 0 auto;
padding: 28px 0 32px;
overflow: hidden;
position:relative;
z-index: -1;
    }

Note last two lines.

Traveling up the dom, I was able to find the container that needed the proper z-index. It was the grandparents of the drop down. Even though all of the parents and children had a higher z-index.