LOFT is a theme designed to be compatible on any device that might access it. With built in Bootstrap3 layouts, the user can organize content in a such a way that it will always present itself beautifully, whether that be on a desktop computer or mobile phone.
Please read this documentation on adding 'Layouts' to a block on a given Concrete5 page if you are unfamiliar with creating block layouts.
When the Layout tool appears, select 'Grid: Twitter Bootstrap' and then select your number of columns from the toolbar. Drag your columns to their appropriate widths and save your layout. This customizability allows the user of an LOFT theme to dynamically create multiple different page layouts using only one Concrete5 page type.