Chrome layout bug

HTML

<div id="playground">
    <div id="panel">
        <div id="panel-thumb">
        </div>
    </div>
    <div id="header">
    </div>
</div>

CSS

body
{
    background: gray;
}
#playground
{
    /* position: fixed; */
    position: absolute;
    top: 50px;    
    bottom: 50px;    
    left: 0;
    right: 0;
    overflow: hidden;
    background: white;
}
#panel
{
    position: fixed;
    z-index: 1;
    top: 10px;
    right: 10px;
    width: 50%;
    height: 30px;
    background: #F0F0F0;
}
#panel-thumb
{
    position: absolute;
    top: 0;
    height: 60px;    
    width: 20px;
    background: green;
}
#panel-thumb:hover
{
    background: red;
}
#header
{
    background: #BBB;
    height: 10px;
    -webkit-transform: translateZ(0);
    -o-transform: translateZ(0);
    -moz-transform: translateZ(0);
    -transform: translateZ(0);
}