Transform makes back side of 3D card unclickable

Question

I want to make flip like http://desandro.github.io/3dtransforms/examples/card-01.html

But with buttons on each side. So here is my html

<div class="flip-container">
    <div class="flip">
        <div class="side front">
            <p>front</p>
            <button class="front-flip-button">flip</button>
        </div>
        <div class="side back">
            <p>back</p>
            <button class="back-flip-button">flip</button>
        </div>
    </div>
</div>

and css

.flip-container{
    position: relative;
    -webkit-perspective: 800;
    width: 500px;
    height: 300px;
}
.flip{
    position: absolute;
    width: inherit;
    height: inherit;
    -webkit-transform-style: preserve-3d;
    -webkit-transition-duration: 500ms;
    -webkit-transform: translate3d(0, 0, 0);
    border: 1px solid;
}
.side{
    position: absolute;
    width: inherit;
    height: inherit;
    -webkit-transform-style: preserve-3d;
    -webkit-backface-visibility: hidden;
}
.flip.flipped,
.back{
    -webkit-transform: rotate3d(0, 1, 0, 180deg);
}
.back-flip-button,
.front-flip-button{
    position: absolute;
    left: 0;
    top: 0;
}
p{
    font-size: 90px;
    text-align: center;
}

And everything is pretty good, but when I use some element with translateZ it makes back button unclickable.

<div class="flip-container">
    <div class="flip">
        <div class="side front">
            <p>front</p>
            <button class="front-flip-button">flip</button>
        </div>
        <div class="side back">
            <p>back</p>
            <button class="back-flip-button">flip</button>
        </div>
    </div>
</div>

<div class="some"></div>

Why is that happening?

http://jsfiddle.net/j5Sm4/

Answer 1

Apply this

.back-flip-button {
    ... Your other styles ...
    -webkit-transform:translateZ(1px);
    -webkit-backface-visibility:hidden;
    /* Needs other prefixes to be cross browser */
}

Demo

This is because the parent element gets its own stacking order. To equalize the stacking order and thus put the button on top, you have to give it a stacking order which I did using translateZ. The backface-visibility:hidden makes the button not show on the front side

In the future we will likely be able to do this by applying the will-change property to the back side