如何仅在水平轴上使用vega-lite链接多个绘图？

{
  "data": {
    "values": [
      {"x": 1, "y": 5, "category": "A"},
      {"x": 2, "y": 3, "category": "A"},
      {"x": 3, "y": 8, "category": "A"},
      {"x": 1, "y": 2, "category": "B"},
      {"x": 2, "y": 4, "category": "B"},
      {"x": 3, "y": 6, "category": "B"}
    ]
  },
  "layer": [
    {
      "mark": "line",
      "encoding": {
        "x": {"field": "x", "type": "quantitative"},
        "y": {"field": "y", "type": "quantitative"},
        "color": {"field": "category", "type": "nominal"}
      }
    },
    {
      "mark": "point",
      "encoding": {
        "x": {"field": "x", "type": "quantitative"},
        "y": {"field": "y", "type": "quantitative"},
        "color": {"field": "category", "type": "nominal"}
      }
    }
  ]
}