Layo
Since this is a one-column layout, the .content is not floated.
Logo Replacement
An image placeholder was used in this layout in the .header where you'll likely want to place a logo. It is recommended that you remove the placeholder and replace it with your own linked logo.
Be aware that if you use the Property inspector to navigate to your logo image using the SRC field (instead of removing and replacing the placeholder), you should remove the inline background and display properties.