.x-tab-close-btn {
    position: absolute;
    top: 2px;
    right: 2px;
    width: 11px;
    height: 11px;
    font-size: 0;
    line-height: 0;
    text-indent: -999px;
    background: no-repeat;
    background-image: url(../../resources/themes/images/default/tab/tab-default-close.gif);
    filter: alpha(opacity=60);
    opacity: .6;
}