All We.Retail pages use the Layout Container component to implement responsive design. The layout container provides a paragraph system that allows you to position components within a responsive grid. This grid can rearrange the layout according to the device/window size and format. The component is used in conjunction with the Layout mode in the page editor, which allows you to create and edit your responsive layout dependent on device.
For further information, refer to the authoring document Responsive Layout or the administrator document Configuring Layout Container and Layout Mode for complete technical details.