.background{width:100%; height:100%}
.backgroundleft{background-image:url(/tpls/img/back/left.gif); background-repeat:repeat-y; background-position:right top; width:50%}
.backgroundright{background-image:url(/tpls/img/back/right.gif); background-repeat:repeat-y; background-position:left top; width:100%}