Each item can span from 1 to 12 columns

Use any combination that adds up to 12 columns to form a row

In this example, the item 1 is starting at column 1 and spanning 3 columns wide, the item 2 is starting at column 4 and spanning 9 columns.

In this example, the item 1 is starting at column 1 and spanning 6 columns wide, the item 2 is starting at column 7 and spanning 6 columns.