In site.css: .row_2 { background-color: #f4f4f4; } .row_1 { background-color: #ffffff; } In generate.pl: ... print "\@import url(/site.css);\n"; my $num_rowtypes = 2; ... my $count = 0; for(my $i=0;$i<=$#{$items_list};$i++) { print "". "".($i+1)."\n"; foreach my $col ("art","tit","yer","cht") { my $val = link_to($cat,$page,$col,$nam); print "".$val."\n"; } print "\n"; $count++; $count = 0 if($count == $num_rowtypes); }