1': 'span 1 / span 1', 'span-2': 'span 2 / span 2', 'span-3': 'span 3 / span 3', 'span 1': 'span 1 / span 1', 'span-2': 'span 2 / span 2', 'span-3': 'span 3 / span 3', 'span