谁知道怎么把博客的背景换成图片吗？

用固定背景代码，效果可见http://blog.sina.com.cn/u/1258350062
代码是：-<STYLE type=text/css>
.bodyTop {background:#transparent} .logo {background:#transparent}
.banner {background:#transparent} .menu {background:#transparent}
.feeds .up {background:#transparent} .feeds .down{background:#transparent} .feeds .function {background:#transparent} .links .up{background:#transparent}
.links .down {background:#transparent} .links .mid {background:#transparent} .photo .mid {background:#transparent} .label .mid {background:#transparent}
.calendar .mid {background:#transparent} .callboard .up {background:#transparent} .callboard .down {background:#transparent}
.callboard .mid {background:#transparent} .bodyBg {background:#transparent} .bodyBottom {background:#transparent}
.sysW770 {background:#transparent} .gbook .up {background:#transparent} .gbook .down {background:#tran