Empty space will be in the direction of main-end and cross-end

A BB CCC DDDD EEE
EE FFF
FFF GGG
GGG HHH
HHH
HHH IIIII
IIIII JJJJ
JJJ
JJJJ

Main-start Main-end

Cross-start Cross-end

flex-row: column-reverse wrap-reverse