title: Doesn't change the Bizcharts Colour
body: <p>I used this <a href="https://bizcharts.net/product/bizcharts/demo/11" rel="nofollow noreferrer">bizchart</a> in my react project, any one know how to change green and blue colour in this chart?</p>
  
  <pre><code>import React from "react";
      import {
        G2,
        Chart,
        Geom,
        Axis,
        Tooltip,
        Coord,
        Label,
        Legend,
        View,
        Guide,
        Shape,
        Facet,
        Util
      } from "bizcharts";
      import DataSet from "@antv/data-set";
  
      class Areanull extends React.Component {
        render() {
          var data = [
            {
              year: "1986",
              ACME: 162,
              Compitor: 42
            },
            {
              year: "1987",
              ACME: 134,
              Compitor: 54
            },
            {
              year: "1988",
              ACME: 116,
              Compitor: 26
            },
            {
              year: "1989",
              ACME: 122,
              Compitor: 32
            },
            {
              year: "1990",
              ACME: 178,
              Compitor: 68
            },
            {
              year: "1991",
              ACME: 144,
              Compitor: 54
            },
            {
              year: "1992",
              ACME: 125,
              Compitor: 35
            },
            {
              year: "1993",
              ACME: 176,
              Compitor: 66
            },
            {
              year: "1994",
              ACME: 156
            },
            {
              year: "1995",
              ACME: 195
            },
            {
              year: "1996",
              ACME: 215
            },
            {
              year: "1997",
              ACME: 176,
              Compitor: 36
            },
            {
              year: "1998",
              ACME: 167,
              Compitor: 47
            },
            {
              year: "1999",
              ACME: 142
            },
            {
              year: "2000",
              ACME: 117
            },
            {
              year: "2001",
              ACME: 113,
              Compitor: 23
            },
            {
              year: "2002",
              ACME: 132
            },
            {
              year: "2003",
              ACME: 146,
              Compitor: 46
            },
            {
              year: "2004",
              ACME: 169,
              Compitor: 59
            },
            {
              year: "2005",
              ACME: 184,
              Compitor: 44
            }
          ];
          var dv = new DataSet.View().source(data);
          dv.transform({
            type: "fold",
            fields: ["ACME", "Compitor"],
            key: "type",
            value: "value"
          });
          const scale = {
            value: {
              alias: "The Share Price in Dollars",
              formatter: function(val) {
                return "$" + val;
              }
            },
            year: {
              range: [0, 1]
            }
          };
          return (
            &lt;div&gt;
              &lt;Chart
                data={dv}
                padding={"auto"}
                scale={scale}
                forceFit
              &gt;
                &lt;Tooltip crosshairs /&gt;
                &lt;Axis /&gt;
                &lt;Legend /&gt;
                &lt;Geom type="area" position="year*value" color="type" shape="smooth" /&gt;
                &lt;Geom
                  type="line"
                  position="year*value"
                  color="type"
                  shape="smooth"
                  size={2}
                /&gt;
              &lt;/Chart&gt;
            &lt;/div&gt;
          );
        }
      }
  
      ReactDOM.render(&lt;Areanull /&gt;, mountNode)
  </code></pre>