如何在vega-lite中定义热图的自定义颜色？

{
  "$schema": "https://vega.github.io/schema/vega-lite/v5.json",
  "data": {"url": "data.csv"},
  "mark": "rect",
  "encoding": {
    "x": {"field": "x", "type": "ordinal"},
    "y": {"field": "y", "type": "ordinal"},
    "color": {"field": "value", "type": "quantitative", 
              "scale": {"type": "linear", 
                        "range": ["#ffffcc", "#a1dab4", "#41b6c4", "#2c7fb8", "#253494"]}
              }
  }
}