Column width issue

Getting help Questions
27 
let nestedHeaders = [
  ['', { label: this.timelogHTableProperties.headerName, colspan: 8 }],
  [
    "Event",
    {
      label: '<div style="width:170px; margin:auto; ">' + (fuelGradeNames[0] ? fuelGradeNames[0] + " / " +
        ((!!namesOfBunkerTanker[0]) ? namesOfBunkerTanker[0] : "") : "") + '</div>', colspan: 2
    },
    {
      label: '<div style="width:170px; margin:auto;">' + (fuelGradeNames[1] ? fuelGradeNames[1] + " / " +
        ((!!namesOfBunkerTanker[1]) ? namesOfBunkerTanker[1] : "") : "") + '</div>', colspan: 2
    },
    {
      label: '<div  style="width:170px; margin:auto;" >' + (fuelGradeNames[2] ? fuelGradeNames[2] + " / " +
        ((!!namesOfBunkerTanker[2]) ? namesOfBunkerTanker[2] : "") : "") + '</div>', colspan: 2
    },
    {
      label: '<div  style="width:170px; margin:auto;">' + (fuelGradeNames[3] ? fuelGradeNames[3] + " / " +
        ((!!namesOfBunkerTanker[3]) ? namesOfBunkerTanker[3] : "") : "") + '</div>', colspan: 2
    },

  ],
  [
    "",
    { label: "Date", colspan: 1 },
    { label: "Hours", colspan: 1 },
    { label: "Date", colspan: 1 },
    { label: "Hours", colspan: 1 },
    { label: "Date", colspan: 1 },
    { label: "Hours", colspan: 1 },
    { label: "Date", colspan: 1 },
    { label: "Hours", colspan: 1 }
  ]

];