HarmonyOS 自定义的Dialog如何不在左右两侧留边距直接填满屏幕宽度

自定义的Dialog如何不在左右两侧留边距，直接填满屏幕宽度？代码如下：

@CustomDialog
export struct CustomDatePickerDialog {
  private controller: CustomDialogController = new CustomDialogController({ builder: CustomDatePickerDialog() })
  private onDateSelect: (selectDate: string) => void = () => {
  }
  private selectDate: string = ""

  build() {
    Column() {
      Row() {
        Image($r("app.media.ic_back_grey"))
          .width(20)
          .height(26)
          .padding(5)
          .margin(10)
          .onClick(() => {
            this.controller.close()
          })
        Blank()
        Text("完成").fontColor($r("app.color.color33")).padding(10).fontSize(15)
          .onClick(() => {
            this.onDateSelect(this.selectDate)
            this.controller.close()
          })
      }.width("100%").height(45)

      DatePicker({
        start: DateUtils.getToday(),
        end: DateUtils.getLastDayOfYear(30),
        selected: DateUtils.getToday()
      }).width("100%")
        .onDateChange((value => {
          this.selectDate = DateUtils.getFormatDateStr(value, "yyyy-MM-dd")
        }))
    }.width("100%").backgroundColor(Color.White)
  }
}

private datePickerDialogController: CustomDialogController | null = new CustomDialogController({
  builder: CustomDatePickerDialog({
    onDateSelect: (selectDate) => {
      ToastUtils.showToast(selectDate)
    }
  }),
  cornerRadius: 0,
  alignment: DialogAlignment.Bottom,
  backgroundColor: Color.White,
  autoCancel: false,
  height: 230,
  onWillDismiss: () => {
  }
})