{
  "$schema": "https://developer.microsoft.com/json-schemas/sp/v2/column-formatting.schema.json",
  "elmType": "div",
  "txtContent": "@currentField",
  "style": {
    "padding-left": "14px"
  },
  "attributes": {
    "class": "=if(@currentField >= 16, 'ms-bgColor-red', if(@currentField >= 12, 'ms-bgColor-orangeLighter', if(@currentField >= 8, 'ms-bgColor-yellow', 'ms-bgColor-green'))) + ' ms-fontColor-white'"
  }
}