如何在Scatter Google Charts中显示两种不同的颜色？

Question

我正在使用Google Charts获取简单的散点图。我想在图表中使用两种不同的颜色。我们如何添加添加到不同的背景颜色。我需要为负片红色添加背景，并为正值部分添加绿色

function drawChart() {
    // Define the chart to be drawn.
    var data = new google.visualization.DataTable();
    data.addColumn('number', '');
    data.addColumn('number', '');
    data.addRows([
        [-0.5, 1],
        [100, 1],
        [-80, 2],
        [25, 2],

        [60, 8],
    ]);

    // Set chart options
    var options = {
        title: 'guilt experience Vs eat satisfaction',
        titlePosition: 'none',
        position: 'center',
        hAxis: {
            title: 'Guilt Valueu00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0u00A0Eat Value',
            minValue: 0,
            maxValue: 15,
            ticks: [0, 20, 40, 60, 80, 100, -20, -40, -60, -80, -100]
        },

        vAxis: {
            title: '',
            minValue: 0,
            ticks: [0, 1, 2, 3, 4, 5, 6, 7, 8]
        },
        legend: {
            position: 'none'
        },
    };

    // Instantiate and draw the chart.
    var container = document.getElementById('chart_div');
    var chart = new google.visualization.ScatterChart(document.getElementById('chart_div'));

    google.visualization.events.addListener(chart, 'ready', function() {
        var layout = chart.getChartLayoutInterface();

        for (var i = -0; i < data.getNumberOfRows(); i++) {
            // add image above every fifth element
            var xPos = layout.getXLocation(data.getValue(i, 0));
            var yPos = layout.getYLocation(data.getValue(i, 1));
            var whiteHat = container.appendChild(document.createElement('img'));
            if (data.getValue(i, 0) < 0) {
                whiteHat.src = 'https://i.imgur.com/LqiTeQI.png';
            } else {
                whiteHat.src = 'https://i.imgur.com/rACTObW.png';
            }
            whiteHat.style.position = 'absolute';
            whiteHat.style.height = '15px';
            whiteHat.style.width = '15px';
            // 16x16 (image size in this example)
            whiteHat.style.top = (yPos) + 'px';
            whiteHat.style.left = (xPos) + 'px';
        }
    });
    chart.draw(data, options);
}
google.charts.setOnLoadCallback(drawChart);

<script type="text/javascript" src="https://www.gstatic.com/charts/loader.js">
</script>
<script type="text/javascript">
  google.charts.load('current', {
    packages: ['corechart', 'scatter']
  });
</script>
<div id="chart_div" ></div>

我想添加不同的背景颜色，如上图像正面部分不同颜色和负面部分不同颜色