How to make div on top of all other control

Question

I want my div to show on top of everything I put 100% width and height and it show above a lot of control except some have css z-index and other things. I tried to set the div z-index to a big number but this did not work.

{
    width: 100%;
    height: 100%;
    top: 5px;
    left: 0px;
    background-color: #FFFFFF !important;
    padding: 10px;
    overflow: hidden;
    visibility: visible;
    display: block;
    z-index: 500 !important;
    position: relative;
}

Answer 1

Since you want to cover the whole screen, I recommend this:

#overlayDiv {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index:99;
}

Note, you don't have to set the display and visibility properties. Also, don't set padding or margin on this element! If you want it to have a padding, set a margin on its child/children.

Also, make sure that the DIV in question is a direct child of the BODY element.