Office-js，如何循环处理Excel工作簿的样式

<script src="https://appsforoffice.microsoft.com/lib/1/hosted/office.js"></script>

Office.initialize = function (reason) {
  // 初始化完成后的回调函数
};

Excel.run(function (context) {
  var workbook = context.workbook;
  // 后续操作
  return context.sync();
}).catch(function (error) {
  console.log(error);
});

Excel.run(function (context) {
  var workbook = context.workbook;
  var worksheets = workbook.worksheets;
  worksheets.load("items/name");

  return context.sync().then(function () {
    for (var i = 0; i < worksheets.items.length; i++) {
      var worksheet = worksheets.items[i];
      var range = worksheet.getRange("A1:D4");
      range.format.fill.color = "yellow";
    }
    return context.sync();
  });
}).catch(function (error) {
  console.log(error);
});