<script type="text/javascript">
var bodyBgs = [];    //创建一个数组变量来存储背景图片的路径
bodyBgs[0] = "https://images.cnblogs.com/cnblogs_com/wjhsmart/1817159/o_2007300516065.jpg";
bodyBgs[1] = "https://images.cnblogs.com/cnblogs_com/wjhsmart/1817159/o_2007300516333.jpg";
bodyBgs[2] = "https://images.cnblogs.com/cnblogs_com/wjhsmart/1817159/o_2007300516461.jpg";
bodyBgs[3] = "https://images.cnblogs.com/cnblogs_com/wjhsmart/1817159/o_20073005302120.jpg";
bodyBgs[4] = "https://images.cnblogs.com/cnblogs_com/wjhsmart/1817159/o_20073005393260.jpg";
bodyBgs[5] = "https://images.cnblogs.com/cnblogs_com/wjhsmart/1817159/o_2007300530559.jpg";
bodyBgs[6] = "https://images.cnblogs.com/cnblogs_com/wjhsmart/1817159/o_20073005310729.jpg";
bodyBgs[7] = "https://images.cnblogs.com/cnblogs_com/wjhsmart/1817159/o_20073005312666.jpg";
bodyBgs[8] = "https://images.cnblogs.com/cnblogs_com/wjhsmart/1817159/o_200730055501158.jpg";

var int=self.setInterval("clock()",10000);
function clock()
{
var randomBgIndex = Math.round( Math.random() * 8 );
document.body.style.background = "url("+bodyBgs[randomBgIndex]+") fixed";
}

</script>