.a1 {  border: #CCCCCC; border-style: solid; border-top-width: 1px; border-right-width: 1px; border-bottom-width: 1px; border-left-width: 1px}
.a2 {  border: #CCCCCC; border-style: solid; border-top-width: 0px; border-right-width: 0px; border-bottom-width: 1px; border-left-width: 0px}
.a3 {  border: #CCCCCC; border-style: solid; border-top-width: 1px; border-right-width: 0px; border-bottom-width: 0px; border-left-width: 0px}