Hi, how to reorder the modules on mobile page,

now it shows
1. Module Sidecol-A, B
2. Module ContentTop-A, B, C
3. Module ContentBottom-A, B, C

i would like switch to
1. Module ContentTop-A, B, C
2. Module ContentBottom-A, B, C
3. Module Sidecol-A, B

thanks a lot~
Rick