Setting opacity on image causes an overlapping element's box-shadow to go away


The following CSS, applied to an <a> and a <div> residing in individual <tr><td> elements in a <table> (with border-collapse and td { padding: 0px; } set), works as expected:

a {
    background-image: url("");
    height: 100px;
    width: 120px;
    display: block;
div {
    width: 200px;
    box-shadow: #000 0px 0px 13px;

If I apply any opacity to the <a>, the browser's internal layering seems to break horribly.

Comparison Note that the test picture's last pixel sits within the <div>'s box-shadow, even in the first example. (And it says opacity = ".99", if you can't see it in the image >.>)

Is this possibly a rendering bug that's managed to creep into both Firefox and Chrome? :P

See what opens and shuts in this JSFiddle.

Thanks in advance!

Problem courtesy of: i336_


Quite Simple.

Thank you for clean formatting.

Change opaque ID to this:

#opaque {
    opacity: .99;

What is happening is whenever opacity is set, the back-end method of CSS3 to interpret it throws some pretty wild z-index's.

Just set it to stack behind the other elements and all will work fine for you.

position:relative; - Cause otherwise it wouldn't accept your z-index property.

z-index:-10; - So that it places it behind the z-index of 0 of your other objects.


The default value of HTML elements does not support static as an object that z-index will apply to, hence the position declaration.

And it totally does with absolute, fixed, relative, or inherit, but not static.

Solution courtesy of: Nicholas Hazel


There is currently no discussion for this recipe.

This recipe can be found in it's original form on Stack Over Flow.