.bl {background: url(bl.jpg) 0 100% no-repeat #660066; width: 137px}
.br {background: url(br.jpg) 100% 100% no-repeat}
.tl {background: url(tl.jpg) 0 0 no-repeat}
.tr {background: url(tr.jpg) 100% 0 no-repeat; padding:5px}