make a div the top layer code example
Example: css element top layer
#overlayDiv {
position: fixed;
top: 0;
left: 0;
width: 100%;
height: 100%;
z-index:99;
}
#overlayDiv {
position: fixed;
top: 0;
left: 0;
width: 100%;
height: 100%;
z-index:99;
}