The alignment must be set manually by using column start and column span, that way the user can position the item exactly as intended with the flexibility doing more than the common start, center, and end alignments.
To align an item to the start, set column start to 1.
To align an item to the center, set column start by using this formula: (12 - column_span) / 2 + 1.
To align an item to the end, set column start by using this formula: (12 - column_span) + 1.
Offset by 1 column from the center.
Offset by 1 column from the start.