ul { padding:0; border-spacing:-1px; flow: "a a" "b c" "d c"; width:*; height:*; } li { display:block; border:1px solid; width:*; height:*;} li:nth-child(1) { float:"a"; } li:nth-child(2) { float:"b"; } li:nth-child(3) { float:"c"; } li:nth-child(4) { float:"d"; }