.bl {background: url(../images/bl.png) 0 100% no-repeat #FFFFF0;}
.br {background: url(../images/br.png) 100% 100% no-repeat;}
.tl {background: url(../images/tl.png) 0 0 no-repeat}
.tr {background: url(../images/tr.png) 100% 0 no-repeat}