zzz_zerolinelayer_below.json

{
 "data": [
  {
   "type": "bar",
   "x": [-1, 0, 2, 3],
   "y": [-1, 2, -3, 4],
   "name": "xy"
  },
  {
   "line": {
    "width": 10
   },
   "mode": "lines",
   "x": [-1, 0, 2, 3],
   "y": [-3, 1, -1, 2],
   "xaxis": "x2",
   "yaxis": "y2",
   "name": "x2y2"
  }
 ],
 "layout": {
  "title": {
    "text": "All zerolines below traces (x/x2: pink, y/y2: black)"
  },
  "width": 600,
  "height": 400,
  "xaxis": {
   "zeroline": true,
   "zerolinewidth": 5,
   "zerolinecolor": "pink",
   "zerolinelayer": "below traces"
  },
  "xaxis2": {
   "overlaying": "x",
   "zeroline": true,
   "zerolinewidth": 5,
   "zerolinecolor": "pink",
   "zerolinelayer": "below traces",
   "side": "top"
  },
  "yaxis": {
    "zeroline": true,
    "zerolinewidth": 5,
    "zerolinecolor": "black",
    "zerolinelayer": "below traces",
    "range": [-1, 4]
  },
  "yaxis2": {
    "zeroline": true,
    "zerolinewidth": 5,
    "zerolinecolor": "black",
    "zerolinelayer": "below traces",
    "range": [-3, 2],
   "overlaying": "y",
   "side": "right"
  }
 }
}