.google-visualization-tooltip {
	background: #111 !important;
	border: none !important;
}
.google-visualization-tooltip span {
	color: #fff !important;
}
span[rel='tooltip'] {
	cursor: pointer;
	display: inline-block;
}
.tooltip
{
    text-align: center;
    color: #fff;
    background: #111;
    position: absolute;
    z-index: 9999;
    padding: 5px;
    line-height: initial;
    font-size: 12px;
    border-radius: 5px;
    -moz-border-radius: 5px;
    margin-top: 4px;
}
    .tooltip:after /* triangle decoration */
    {
        width: 0;
        height: 0;
        border-left: 5px solid transparent;
        border-right: 5px solid transparent;
        border-top: 5px solid #111;
        content: '';
        position: absolute;
        left: 50%;
        bottom: -5px;
        margin-left: -5px;
    }
        .tooltip.top:after
        {
            border-top-color: transparent;
            border-bottom: 5px solid #111;
            top: -10px;
            bottom: auto;
        }
        .tooltip.left:after
        {
            left: 5px;
            margin: 0;
        }
        .tooltip.right:after
        {
            right: 5px;
            left: auto;
            margin: 0;
        }