老师帮忙检查代码，顺便问个问题

<!DOCTYPE html>
<html>
    <head>
        <meta charset="utf-8" />
        <title></title>
        <script src="https://cdn.bootcss.com/Chart.js/2.5.0/Chart.js"></script>
    </head>
    <body>
    <!-- 此处填写代码创建canvas标签 -->
    <div style="width: 600px; height: 600px;">
        <canvas id="myChart"></canvas>
    </div>
    <script>
        var ctx = document.getElementById('myChart');
        //此处填写代码
        var data = {
            labels: ["事业", "财运", "爱情", "人缘", "健康", "友情", "亲情"],
            datasets: [{
                    label: "差",
                    backgroundColor: "rgba(179,181,198,0.2)",
                    borderColor: "rgba(179,181,198,1)",
                    pointBackgroundColor: "rgba(179,181,198,1)",
                    pointBorderColor: "#fff",
                    pointHoverBackgroundColor: "#fff",
                    pointHoverBorderColor: "rgba(179,181,198,1)",
                    data: [65, 60, 70, 30, 70, 55, 40]
                },
                {
                    label: "良",
                    backgroundColor: "rgba(255,99,132,0.2)",
                    borderColor: "rgba(255,99,132,1)",
                    pointBackgroundColor: "rgba(255,99,132,1)",
                    pointBorderColor: "#fff",
                    pointHoverBackgroundColor: "#fff",
                    pointHoverBorderColor: "rgba(255,99,132,1)",
                    data: [30, 19, 40, 50, 20, 27, 96]
                },
                {
                    label: "优",
                    backgroundColor: "rgba(14,255,110,0.2)",
                    borderColor: "rgba(14,255,110,1)",
                    pointBackgroundColor: "rgba(255,99,132,1)",
                    pointBorderColor: "#fff",
                    pointHoverBackgroundColor: "#fff",
                    pointHoverBorderColor: "rgba(14,255,110,1)",
                    data: [30, 48, 100, 90, 20, 28, 40]
                }
            ]
    };
        var options = {
            title: {
                display: true,
                text:'2017年运势表'
            }
        };
        //此处填写代码
        var radar = new Chart(ctx, {
            type: 'radar',
            data: data,
            options: options
        });
    </script>
    </body>
    
</html>

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