I have used the pop up described above and it works well. The only thing I see that I have a blue coloured page header div (width 100%, height 200px, z-index:9998).
I have a series of images below that on the page. The pop up triggers when an image is clicked. However for some reason the pop up window is popping up under the page header div when an image near the top of the page is clicked.
How can I make the pop up appear over the top of that header div?
If I need to set the z-index of the div, where do I set it and on which element/class?