<!DOCTYPE html> <!-- webkit-test-runner [ useFlexibleViewport=true AsyncOverflowScrollingEnabled=true ] -->
<html>
<head>
    <meta name="viewport" content="width=device-width">
    <style>
        body {
            -webkit-overflow-scrolling: touch;
        }
        
        .box {
            height: 100px;
            width: 100px;
            background-color: blue;
            position: absolute;
            top: 0;
            left: 0;
        }
        
        .stacking {
            position: relative;
            z-index: 0;
        }
        
        #log {
            margin-top: 120px;
        }
    </style>
    <script>
        function doTest()
        {
            var box = document.getElementById('test');
            var computedZIndex = window.getComputedStyle(box).zIndex;
            var result;
            if (computedZIndex == 'auto')
                result = 'PASS: computed zIndex was auto';
            else
                result = 'FAIL: computed zIndex was ' + computedZIndex;

            document.getElementById('log').textContent = result;
        }
        window.addEventListener('load', doTest, false);
    </script>
</head>
<body>
    <div class="container">
        <div class="box" style="background-color: orange; z-index: 0"></div>
        <div id="test" class="box" style="background-color: green;">
            <div class="box" style="background-color: red; z-index: -1"></div>
        </div>
    </div>

    <div id="log"></div>
</body>
</html>