In Colorado they created districts that cut out strong republican areas, put them together in oddly shaped districts gerrymandered to build districts that would no longer be contested but would be sure victories for the democrats. This had a combined effect in that it created rural districts that have fewer representatives than they had before when there were more fairly structured districts, and they got a majority in both houses of the legislature for the past two elections after their gerrymandering. This created fewer districts with votes that would go like 75% for republicans, as they carefully cut them out of districts where they were often winning by close votes 52% to 48% and the like and gaining one or the other house of the legislature....
What the courts are enforcing is to have Alabama create carefully structured districts that will ensure that there are two districts with majority black voters. The courts are carefully creating oddly shaped districts to give one historically underrepresented group an advantage in more than one district, while Alabama was demanding that the district they constructed that ensured one district only was the way to go. The SCOTUS, largely made up of conservatives, decided against Alabama in this case.