Echarts rewrites the data view, how to modify the added class without effect?

const getTable = function (opt, xName, yname) {
  console.log(opt);
  const axisData = opt.xAxis[0].data;
  const series = opt.series[0];
  let table = `${"<table class="ccc"><thead><tr>"
    + "<th>"}${xName}</th>`
    + `<th>${yname}</th>`;
  table += "</tr></thead><tbody>";
  for (let i = 0; i < axisData.length; iPP) {
    table += `<tr><td>${axisData[i]}</td>`;
    table += `<td>${series.data[i]}</td></tr>`;
  }
  return table;
};

the class="ccc" here doesn"t work? Is there something wrong?

Nov.02,2021
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