el-popover怎么设置宽度

<el-popover
  ref="popoverRef"
  :virtual-ref="buttonRef"
  trigger="click"
  :title="t('Hideandshowcolumns')"
  virtual-triggering
  :hide-after="parseInt('10')"
  :transition="popoverTransition"
  width="300px"
>
  <!-- Popover 内容 -->
</el-popover>