u-parse loadingImg占位图尺寸如何设置

<u-parse :content="data.MtlDescription" :preview-img="false" :lazy-load="true" loadingImg="https://www.sucaijishi.com/uploadfile/2014/0524/20140524124233131.gif"></u-parse>

里面loadingImg这个尺寸如何设置，一个晓得加载gif，放上去放大到全屏了