一个1x1px大小Data/Base64数据的gif透明图片
<
img
src="data:image/gif;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVQImWNgYGBgAAAABQABh6FO1AAAAABJRU5ErkJggg==" style="width:20px;border:solid 1px #999;" />
