it looks as it did
= it looks (today) the same as it looked (then)
looked --> 用 did 代替 looked
or
The tower has been rebuilt so that it IS now as it WAS during the 12 century
it looks as it did
= it looks (today) the same as it looked (then)
looked --> 用 did 代替 looked
or
The tower has been rebuilt so that it IS now as it WAS during the 12 century